1. Yes, the timing is disappointing the day after burger game, but let's look at it from his POV. He is embroiled in chasing high school title dreams in the latter part of his senior season. Mom and coach bring up professional idea. He dismisses it. Has playoff games and McD's on the horizon.
A couple weeks pass and they bring up G-League by name. Idea has been bumping around his skull all the while. Now it's really late in the season and he still has these pending commitments., but is intrigued.
Enter a bag man...POSSIBLY. Now there is more incentive. Maybe even Adam Silver or other NBA person gives him a wink-wink just do it kid, we got your back and won't let you be a martyr. Now it's like a week before the McDonalds game. Do you really expect him to pull the plug on SU now? No. Stay the course, enjoy the trip and game and then announce.
2. Why didn't he tell/ask/discuss the idea with JB months or weeks in advance if indeed he had decided that early? WHY WOULD HE?
Rule #1 - protect your own interests first at all costs. Your employer won't. If you accepted a new job, gave notice, and then got a new offer would you really ask your new boss-to-be what they thought and what you should before you even started working there? No, you would not.
This altruistic notion that he should have told the coaches weeks ago is simply the misplaced butthurt disappointment of fans. It sucks he is not coming because I think he truly would have opened up the offense for the whole team, but it is what it is.