As you can see, the bech address is starting with "bc1qq" which doesnt seem to be valid. I also had no luck in getting my private key to resolve to the p2sh address.
It is an invalid address.
I had already sent some coins to my seemingly invalid p2sh/segwit addresses - are these coins now entirely lost?
None of the addresses you've shared have coins. I assume you meant - 3JKyqNxb5Wb9uh5NUX4S5PhMZTddEiY92n - as p2sh-segwit, and as anyone can notice from a block explorer it has never received any coins.
In your own case, you sent your coins to an invalid address, it is lost forever.
You can't send coins to an invalid address. An address is (usually) the base58 encoded version of the single-byte prefix, a 160-bit hash and a 4-byte checksum. If the address is invalid, then it means decoding it will not result in an acceptable locking script.