I would say that any trigger for that setup would simply act on the lever so that it pushed it forward. I don’t think that is intended to be the trigger for you finger.
very cool ,on the second video looking at the picture will the barrel go to the right or left?the reason i ask is if it goes to the right the trigger has to be pressed forward to shoot?
Judging by the noise at 15 seconds in the first video were not the only ones impressed with this 😆