The unfortunate fate: Death by dismemberment, evisceration, plasma burn and shotgun shell, following demonic invasion. Oh, and possession too. Followed by more shotgun death.
Was it their fault? In the original games, not so much. If simple teleportation was grounds for Hellish retribution, the entire crew of the Enterprise would be nestled away in Satan’s lower intestine right now.
In Doom 3 though? The entire Martian facility is made up of such Comically Sinister Everything™ that it’s impossible to imagine anything occuring there could ever turn out 100% horror-free. It’s perpetually gloomy. Everyone is terrified, depressed or losing their mind. Industrial accidents are ten a penny, disturbing noises drift down every corridor and the chief scientist is one Dr. Brian Elzebub*. Teleportation experiments in that place were only ever going to lead to one location, and Mr. Tumnus certainly wasn’t going to be waiting at the other end.
*Okay so he wasn't really, but he might as well have been