If A3 goes belly up:
1. It's unlikely that any *A carrier will honor A3 miles. They have no value to other carriers and they've basically been paid for.
2. It's even less likely that any *A carrier would status match.
This isn't the same situation as a more global carrier where there's an affirmative business case for Carrier A to honor Carrier B's program.
I can't predict the future better than the next person, but I can assure you that I wouldn't be transfering or crediting points to A3 until the crisis is resolved, if it's resolved.