+1 with FMB, with out pictures or looking at it is super hard to tell you if it will work fine or not.

My best guess is that probably the 1st 3 or 4 theads are not good but if that thing is ok deeper than that you wont have a problem if you can get somebody to tap that again.

Second option, you can do your own tool but you will need an old cup and then file like 4 slots around. We did one like 20 years ago using a shimano dura ace cup because the steel was super sharp and super hard. Just an idea ok? but is your call.

Hope you find somebody with the tools.