Nobody knows for certain if Jerry is intent upon retaining JG as his HC or actually following up on his proposed intention of not extending him if he fails to deliver a conference title. He has fudged on his promises before.
Conversely, it's also not too difficult to imagine him making excuses to keep him in tow, either. In either case, it'll be interesting to see what transpires if and when a conference championship fails to materialize, as is quite likely.
It's fair to anticipate a firestorm of criticism being in store for him as a result of a failure to release his favorite HC. That's no stranger to JJ, however. This drama will continue to unfold, without a doubt.