I doubt a man with an OC resume like Norv is going to go to the Jets and deal with that utter mess of a QB in Sanchez.
He's 60. He's going to want to work with a good QB and doesn't have time to groom another QB. Sanchez would be lost in the Coryell system anyway.
Plus, the odds are high that Ryan only lasts one year. The new GM will likely want his own HC. Also no way the Jets can produce enough with Sanchez at QB to save Ryans job, let alone Sanchez saving his own job.