I'd need to see some sample code, and would be good if you could reclarify your concerns - So that I understand, from what you've described so far - You have a Record from table A, that holds a recordID of a record in Table B in a Link Field, that then you'd like to return attachment details from Table B of that Link Field recordID?
If I'm correct in understanding, for similar problems I've had to do a two step to dig into Link Field records - I don't think it's uncommon (and I don't believe there's any alternative method, but keen to understand if there is).
Often, I am working 3 tables deep - Project record in the first table, Task record in the second table, and a Task Dictionary record as the third table, so two Link fields and 3 tables worth of RecordIDs does take a bit of skill to master. 😅