Not true. Derby, yes. But rumours of a Sunderland bid first became public on August 17th.
http://www.sunderlandecho.com/sport?articleid=3120280
Until then there were murmurs among Sunderland fans "in the know", but that's it. "Every single fan" knew nothing about a Sunderland bid until around that time. Neither did Kenwyne.
He threw his toys out few days later.
http://news.bbc.co.uk/sport2/hi/football/teams/s/southampton/6962283.stm
And the deal was done in a week.
http://www.socawarriors.net/forum/index.php?topic=30441.0
It's truth. The Sunderland bid was initially hidden from him. The board was told he didn't want to leave. Rumors of the bid came up, Kenwyne started asking questions, felt he was lied to, went on strike.
Here are peopl with personal access and information:
http://www.socawarriors.net/forum/index.php?topic=30335.msg346776#msg346776
http://www.readytogo.net/smb/showpost.php?p=4571173&postcount=33
There was more behind the scenes that most people know.