There are so many three digit numbers, and they are all possibly test subjects from this lab. I don’t know if it’s a coincidence, but Syphus 590 has three digits in it. Syphus could have been a test subject to whatever these experiments are. Although, it doesn’t make sense that the username to the apple II was Syphus 590. My next theory might be a little far-fetched, but the secret area you found under the stairs could be a hideout made by Syphus to hide from the experiments. The apple II could’ve been used to hack into the chat logs to see what experiments were being tested on other people. The experiments he went through could’ve ruined his life, and he wants revenge for it. He’s breaking in and looking around for evidence to find who ruined his life. All of the things you’ve found in your studio could’ve been planted by someone else, maybe D or whoever Nelson is. They could’ve been planting it all around to hide the evidence of the experiments they’ve been doing on people. But when Syphus saw that you guys started finding this stuff, he tried to take it to for evidence or clues. Then there’s the liquid that Syphus injected into himself. When experiments were tested on Syphus, it could’ve given him a medical condition that needed a specific type of medicine to help with. These vials of liquid could be the only thing that’s keeping him alive.

There are so many other things that don’t make sense if this was true. Why did Syphus set up a camera? What’s the deal with the car? And the computer that wouldn’t allow you to call the cops?

The “police officer” the emailed you, and said that Syphus is “the only one left” could be referring to the only test subject still alive.

Maybe Syphus isn’t the bad guy here, maybe you’re seeing this story play out in the wrong perspective. Maybe D or Nelson is the real bad guy here. They’ve been testing subjects, and quite possibly killing them for the sake of science. What were they trying to do with the experiments anyway?

TL;DR Syphus isn’t the bad guy, he’s only looking for revenge