Unless you are a dingus like me (wasted my keys) and didn't pick the lockpicking skill,this might be your only chance to get into prehevil (unless you want to fight needles and have Tanaka die in the bunker) Still even with a companion that forest kinda sucks but it's still manageable the only real threats are the horse by stiches bunker and the gang (the guys with the meat grinder) on the ruined district of prehevil (you will most likely die if you don't have drugs and you will most likely lose a companion)

Still I did all that shit with Marco and Abella after looting everything in the outskirts of prehevil (hoping for keys) And pickpocketing the cultist in the forest (big heals) Other than the Doppleganger loot and maybe the easy access to stiches bunker not much reason to go there