On top of that, he had been getting 3rd string reps all season up until that week, when he got 2nd string reps. So,
basically, we have no idea what he looks like when he has had a chance to knock the mission rust off and develop chemistry with the receivers.
On top of that, Conover's trend in that game was what you would hope for. After missing on 4 of his first 5 passes (and that one completion was a 2 yard pass to Gunner Romney), he then turned around and completed his next 4 passes before ending on a final incompletion. That showed improvement and that he was able to perform better once he got more comfortable.
It was not a good performance overall, but it also was definitely not enough to draw any conclusions about him.