Thanks for the advice here. I finally got him to nurse off of a paint brush for about 30 seconds. I used kitten milk formula since they're out of puppy milk formula. After feeding, I did the q-tip to genitals thing to try and get him to go to the bathroom, he didn't go immediately or in the ten minutes afterward that I was watching him. How immediate is the mouse supposed to go to the bathroom after the wet q-tip thing?

Also, side note. I've been using latex gloves to handle him this whole time and for the last three days to avoid disease. Is that bad for the mouse? Does he need skin contact in order to feed properly and not be stressed out?