i found the last enemy!
first i used a explosive barrel that i put on myself wich for somereason launched me high enough to get over the wall,
but now i found a easier method. basically go into windowed mode and squish your window wich sets it to like a super high view distance mode and that allows you to see the enemy from the locked off area,
you then just need to die and can switch to it. it also is in a very advanced parkour area, i cheesed it a bit with gibs from my space flight but i mysteriously exploded after getting caught between a wall and platform it seems. looks like i need to do it legitimately this time