First off, I can tell you kinda about this b/c I grew up in roach infested houses; we only barely got rid of the bugs for good 5-10 years ago before my mom died. (And the bugs ruined at least one PSX back in the day, ugh.) We had to get a exterminator so this is no joking matter.
Always assume it's german cockroaches; those are the WORST and they can be hell to get rid of. I'd put that PS4 into a box and put it in a garbage bag, with roach traps and put roach gel on all the vents, and seal it up for 5-6 months. If PS4s can stand cold (I don't think they can, but don't yell at me if I'm wrong) you prolly could put that sucker in the freezer a week, but I wouldn't because I don't know if that'll hurt the hdd. Make sure you look up the online manual before you freeze that to be sure, or call Sony and ask.
After that, crack that sucker open (outside, of course. If you froze it, wait until it warms up) and give it a thorough clean to get rid of any dead bugs/bug poop/etc. Make sure you know what you're doing of course. Once it's back together it should be fine.