after deathwarping with the monkey, you'll need to hold right and mash 2 (at about 2-3 cps, nothing too fast) to clip through the entrance. you'll want 1 or 2 grapples for the first loop, so you can make it to the cutscene trigger to the left easily. after the cutscene, die as fast as possible. then you'll want to repeat the process but get 2 or 3 grapples instead, to get near the middle of the room and use your invulnerability to murder monkey man