Great theories. Here is the exact format I wrote it in, but I changed all the characters. I do remember maybe converting it to hex or binary, or at least considering it.
0486 | 4AE5 | 41BC
A58F | 3FBA | 1AD7
34F6 | 2AEB
37A4 | 4AAF
7?A4 | ?42? | 6F?? | ??D8
71?D | 6?A? | ?FCA | 86B?
32?F
7F?B
It is very likely that the ? characters are actual Hex characters that you need to fill in. Filling these in would be up to you. Try looking for patterns you can see in the key that could explain the “?”s.
Once you have a 80 character HEX string, you can try encoding it to base 58 to obtain potentially a WIF compressed key for your wallet.
https://appdevtools.com/base58-encoder-decoder