I have a similar issue. What I've found useful is to shrink my thumb before bowling. To do this, I use 2 Vise Vinyl Thumb Inserts. One is slightly smaller than my expanded thumb size, and the second fits my ideal non-swelling thumb size. I use the first to partially reduce the size, and the second to then bring the thumb size down to what comfortably fits in my ball.
I've used this technique for years and it works well. It's especially effective if you don't like using lots of tape in your thumb hole. Give it a try. At worst, it's a cheap experiment.