Although there were some players who wanted to file complaints, there were some who did so before the big reveal happened. Those players were left in the dark, as they were split, appeared from the remainder of the players as different types themselves. Those who did not leave their rooms and did file those complaints got the reply that, while everything is player driven, death has consequences, and they were paying them. They chose that action, and what they got was the price for it, as it was stated within the terms and services that they signed. These were the first players to realize something, that the game world they were entering was not truly called The Decagon at all. The game world and the 'reality' they logged out into, that as a whole was The Decagon itself, as the game world was just the game world.
It was only once the reveal was made that the connection was made, that the game world they were logging into did not actually have a name of its own. They just assumed that it was The Decagon, because that was the game they were supposed to be beta testing. However, that was not the case, as the title of the game refers to before what they were logging into and what they thought they were logging out of. When, truthfully, they were just logging out of one layer of the game into another layer of it. This was a shock that led some players to just stop playing entirely, and others to just stop altogether, as they just could not take the news. This causes their mind to shut down and remain dormant as a result. It was strange, as they were still present and accounted for; however, there was currently no one home behind those vacant eyes of theirs.
There were a lot of players who were like this, as they were just there, both in the game world and what was now their reality. They were also of all ages, as there was no overall set age for all the players, either. They were not all within the same age range, as they vary from the young to the very old, as The Decagon was being billed as a game for all ages, after all. Thus, they did go about getting a variety of ages to join. The ages ranged from ten to eighty, and there were just a few from the lower or higher ends of the spectrum, either, as there were enough that they could have group samples of every age range between ten and eighty, after all. Though there were kids who entered into this on their own, others were given their spots by others as gifts or as a result of them not being able to do so themselves. Then there was a family that was doing it together, thinking they could just meet up in game afterwards. They were underestimating just how much everything being random would make that, as all players, regardless of age, were placed within the ten different areas at random. There was no rhyme or reason to how they were split, appeared, and placed into the areas they were both in the facility, and what their starting areas would be. Also, they were not told just how far each starting area was from the others, but they were informed that they were scattered across the game world itself.
Parents finding kids, and kids finding parents, became the goals of many players. Did not matter if it was in the game world or within the facility; they were looking for them. That was the ones that did not stop altogether once they learned of the truth of The Decagon. Then there were those that, even before that, when they learned just how truly randomly they were split apart, can could not handle it at all. They just stopped looking altogether and just quietly existed within their own rooms, not leaving them for any real reason anymore. Others were lashing out, and that got them labeled as Player Killers. As a result, sometimes, because they were in game and the wrong person just pissed them off at the wrong time. Thus, they felt the full reign of their wrath at that point.
As for how no player realized that they could not be harmed physically while within the facility, that was because of how things normally were. Harming another person, even if they were a complete stranger, to that degree, was something that was normally done. People do not just randomly go around critically injuring others on a whim that offer, after all. Annoy them to no end, to the point where they could attempt to make a living and even a career out of it. Those time of people were weeded out very early on, as Kynatech was not looking for those types of people to take part in this beta test; however, there were some exceptions to this, though. They allowed only those who agreed to numerous rules that applied only to them, as this was to ensure that they would follow the rules and do not do anything that they were not allowed to do. This is all before they became part of the ten thousand and nine beta tests.
However, there were those who did not pay attention, merely forgot this, or were just straight up lying just to get in on the beta test. Of course, they thought they were being sneaky, but these were the type of people who, when presented with the contract they had to sign, they did not read it. Those who did and rejected, they left, yet still some of them still attempted to do something they were not allowed to, as a person who made it that far. Kynatech, at that point, did not need to make an explanation out of them, as there was no need to do that when there was already a system in place that viciously and brutally counters them. If they can not tell the difference between whistblowing and mere leaking, then they learn, as everything they do or plan to do leaks, while what they were attempting gets neutralized before it can ever go viral or get taken seriously.
This would not be done out of malice or malicious intent either, as they were given a warning, not once...not twice...but thrice. If they choose to ignore the last warning, then what happens next is on them, as Kynatech does not have leaks, as they have controlled the release of information. An entire division devoted to just controlling and managing information, and preventing it from getting into the hands of those that they do not want it to.