Yeah, those stats are still better than Pickett, barely:  a 72.4 passer rating versus Kenny's 66.7.  Impressive.  And Rudolph's last start wasn't "decent," it was a **** performance against one of the worst teams in the league last year.
You're trying to use Pickett's 3+ game sample size like it's the gospel.  The guy is a rookie.  Three of those interceptions came in his first NFL action against the Jets, after his coach gave him zero preparation time.  Rudolph had already been in the league for over a year before he played a single down.  You don't see a difference there?
Don't worry, bud.  Your nephew will get a chance to compete for a starting job somewhere else next year.  And wherever that is, he'll most likely settle into the career backup role he's carved out for himself.  After all, $4-5 million a year to carry a clipboard and never get hit is a pretty good gig.