If I understand your process correctly, it looks like you did a one-to-many comparison for yourself, identified A1 as the strongest link to you, and then did a one-to-many using A1's code. That would not be a good way to work.
Let's say you and A1 are 3rd cousins, then you each share one pair of g-g-g-parents out of 8. Anybody who matches A1 to the same degree will only have a 1/8 chance of being related to you at all.
The better way to follow up is to do a "people who match one or both of two kits". That will immediately list anybody who shares DNA with both you and A1, and what amazed me was that it looks like there is only a single person at the default settings.