Who’s the Saints interim HC if/when a firing occurs?

Yes - that is a concern. If they blame the injuries and run it back with DA again, what a dark lost season that would be. I think it would drop interest and excitement in the team down to levels last seen during the Ditka era.
We already wasted 4 seasons post-Brees. I can't imagine another one is going to hurt. Especially, if you fire a coach and your top 2 candidates pick other teams because they aren't $-97 million over cap and be forced to carry a QB's contract since it was designed to give you cap relief