I would believe it, except for reasons 1 and 4, which I stated in post 16.
Nope - There are plenty of ways to indirectly put the word out that UBL is in Iran (without the need of directly exposing Intel sources in the least).
And we are doing just this regarding the Pak border regions if you read between the lines -
He's in the Pak border region (along with Zawahiri, M. Omar, J Haqqani and G Hekmatyar) - UBL would never put himself at the mercy of a centralized Gov't...especially when their is no need for him to do so -
And as Dog said above...there is no benefit whatsoever for Iran in housing UBL...other then an assured military strike from the U.S. (with the full backing of the American public....which we don't have without UBL being there).