I think Howard was just doing damage control there since he knew that there were many Laker fans. He gave the same sort of lip service in Orlando and then bolted anyway. I don't believe it was all just Kobe for him. I think he looked at the salary they paid Kobe and the fact there was no good young talent to play next to and decided to go where he didn't have to wait.
But name the big time free agents the Lakers have signed since Howard left.
What could he have to gain by not being honest? Why does he care that there are a lot of Lakers fans? It's not like Lakers fans were going to cheer for him on the Rockets.
I think the only issue Dwight had with Kobe coming back was that apparently, in the meeting when the Lakers tried to re-sign him, he asked Kobe how much longer he thought he could play and Kobe said 3-4 more years. Dwight is about to be 30 years old and has made it no secret that he wants to be "the man". He knows that as long as Kobe is a Laker, he'd never be seen that way. So, if Kobe did play 3-4 more years, he'd be 32 or 33 and starting on the downside of his career before he'd be seen as "the man".
End of the day, whatever his reasons, it doesn't matter because he's gone. There are a lot of high end FA's coming up over the next couple of seasons and I'd say it's pretty likely that the Lakers will get a couple of them.