If it's me, I'm taking the invite. The Shrine game was nice, but the Senior Bowl is basically the NFL equivalent of a coaching convention. All the teams' staffs and GMs are in town watching practice and talking to players.
That said, I also get why he'd decline. He had a nice week and game, and as far as we know he made it out healthy. Add what will hopefully be good performances at the combine and UL Pro Day and he's done a lot to help himself. But like I said, if it's me, I'm there. I want to get in front of as many eyes as possible and show teams that I'm more than what's on film from the last 2 years.
Of course, I'm me and he's about to start an NFL career, so what do I know. I don't blame him for trusting his agent.