Honestly, I have no clue what thimbles are for. But I realized at some point this year that instead of using some hard surface to push my needle through assy material and/or hurt my finger pressing too much, I can just… Use a metal thing that sits on the right spot.

Also I know this sounds weird but go to a shop and try them on. It’s weird how much a good fit helps.

The cutting out would probably be the way to go. I mean you could flap it, so it stays connected to the right spot, maybe it’s time for you to be brave and risk it. Especially since you have a sewing machine! That means the seam can turn out quite nice when put back in place. Anyway, good luck and updates are appreciated!