seems like a penis abdominal bump would be physically impossible.
the vagina is set under and behind the uterus, bladder and pubic bone
not to mention the abdominal muscles, natural fat layer, internal support structures and the pelvic diaphragm. internal organs are packed tight, without much shifting about room.. if you did penetrate deeply enough to push into the abdominal cavity, the video clip would end with the female model bleeding out.
deep anal penetration might be possible. i mean, you can see the light on a colonoscopy. so, maybe?
eta: even while fisting my female partner, i've never seen the bulge.. maybe a slight rise in the lower abdomen if she is laying on her back.
a fist/portion of my forearm is certainly larger than most of the peens on LPSG. so i am guessing maybe i would have seen if actually possible.