I'm a genius! I figured out a way to instantly get unwanted gallery thumbnails of deleted images off of profiles. Others may have found this out for themselves but I saw complaints about it in the forum with no answers, so here's what worked for me. (I'll put it in the forum too.) 

In the gallery with deleted images, rearrange the order. I moved everything up one, towards the front as if shuffling the unwanted image to the back. It worked and the thumbnail -filled or a blank '?' had fucked off! 

Thank me with boobies ;p