It's easy they have more than enough technology.
High speed 4k or even 8k cameras and TV's that are reviewable by refs.
Implementation of an artificial intelligence that watches the entire field for penalties and a head ref who watches that from the booth to step in and tell the ref on the field to drop a flag so it can be done in real time or to tell the AI that it's not a proper flaggable offense.
An ethical commissioner who says player safety and means it will step in when all those safeguards fail to replay a down if there is a complete breakdown in proper officiating.
Officials that are not paid by the league but by the teams as a collective, thus no way for any bias towards the NFL.
Restart the officiating crews from scratch with those who messed up last night being permanently banned from any saints game, if not outright fired altogether.
I think that's just a start and I may honestly see if I can get my hands on some AI software to do just what I said.