Is this all that surprising? Bischoff and Vince buried whatever hatchet there was when Bischoff came to the WWE and he was a GM on Raw for years. He was a great heel for the WWE for years and probably would still get major heat if he returned.
My guess is WWE will induct him into the HOF with mainly talking about his accomplishments within WCW, and building up NWO, but he did a great job within the WWE too.