Well, it comes down to being your decision as to how conservative or risk-taking you want to be.
Your problem is caused by GH stimulating growth which has resulted in nerve compression.
Stimulating further such growth will worsen the problem.
There may be a dose that is useful for your other concerns but which won’t stimulate growth in any ways that will further compress any nerves already having such problems. Or there may not be.
Generally speaking total doses per week of about 10-12 IU usually don’t cause carpal tunnel or neuropathy (nerve pain.) However that is in subjects who weren’t already suffering the condition, and likely weren’t right on the edge of it either, and who therefore likely had a margin of error, so to speak. You are not in that position. You have no margin of error.
So it might be that you could get away with total weekly dosages such as that, or maybe not.
Myself, I did not get carpal tunnel from 4 IU/day of GH use, but did get other neuropathy. Even with stopping completely, it took many weeks for it to go away. Of course I have no way of knowing if it would have gone away at the same slow speed, or would have continued, had I dropped to a protocol such as you are using now.
Some say that pyridoxine (Vitamin B6) helps. This was not the case for me, but who knows, can’t hurt to try it. But if you were already getting plenty of pyridoxine in bb’ing related supplements, yet more would I think be extremely unlikely to do anything.