The paper towel trick worked! What I did was:
(1) Had the kid hold the paper towel on their face while I used a fat-tipped washable marker to mark their eyes, nose, mouth, chin, and ears. The nose and chin weren't really necessary. What was necessary was marking their ears!
(2) Put the mask on their head and use the ears to line up the paper towel template. Then I colored back and forth on the eyes and mouth long enough for the marker to seep through the paper towel to mark the mask. It helped to have another person looking to make sure the mask and template were not crooked!
(3) Used scissors to make slits for the eyes and then had the kids test to see if the eyes were good. Then I let them draw their eyes and use scissors to cut the out.
Our papier-mâché was pretty thin, since most of the kids didn't do many layers. It wasn't too hard to cut out the eyes.
Thank you all so much! You were true lifesavers today!