Try dropping your oven temperature by 25 degrees, in addition to using the wet strips.
AI have yet to try this trick but instead I use a flower nail. Just grease the flower nail and place in the center of your pan with batter and bake it works like a charm! Sometimes if you notice a small hump just use a clean cloth and press down to evenly flatten immediately after removing from the oven. I hope this helps you it's sure helped me!
AHow deep are those pans?
sometimes to avoid a hump, i cool cakes upside down. on a parchment
I always only use wet towels. I make sure that they are wet with cold water, and not dripping, but almost. I also bake at 325. I get nice flat cakes every time, even with a 10 inch pan.
Try one layer with, and one without the towel for a true controlled experiment! Have you made the same recipe previously without the towels? This may be less domed than it would be have been with no towels. Those look like pretty deep pans, so it may also help to lower the oven temp and use heat core nails. Some recipes rise a lot and need to be leveled no matter what you do.