Illinois went through similar circumstances with Beckman and handled things about as badly as things could possibly be handled.
They waited to fire Beckman until a couple weeks before the start of the season, despite the investigation beginning towards the end of the prior season.
They let the AD stay on until the middle of the football season before deciding to fire him, too.
They didn’t immediately hire a replacement AD, but instead let their interim AD extend the interim head coach one year.
Then, just before the start of spring practice, they finally hired their new AD and forced him to decide whether to go another season with a lame duck interim or try to make a long term hire outside the normal coach hiring cycle.
Illinois basically lost three recruiting classes and ended up with Lovie Smith as head coach. He wasn’t able to fill out his staff with great options because of the off-cycle hire and wasn’t able to improve the staff in his second season because he had to assure his original staff that they’d get more than one season to get them there in the first place. So by his third season he was still trying to rebuild his staff while coaching essentially a ju-co team of only freshmen and sophomores.
Smith got a lot of criticism for his time at Illinois - much of it deserved - but he moved that program from full on dumpster fire to a merely bad football program.
So, to not repeat the mistakes Illinois made, NW got a good start by dumping Fitz now instead of waiting longer. Now, NW needs to fire its AD immediately and have the new AD in place well before the hiring cycle for a new HC starts in November.