The Shamasters Dr Who event with Tennant has all the hallmarks of a hastily arranged fundraiser. All this "we've been planning this event for 6 months" is utter hogwash. One announced guest to show for 6 months of planning? Event announced only 2 months before it's due to go ahead? Yeah, right. Jog on, Joiner. No one believes you.
I suspect Tennant has severely blotted his copybook with Sean Harry though. If I was Harry, I would NOT be happy with Tennant. It's Harry's own fault for not getting DT tied to an exclusivity contract. He should know Joiner's been pulling these kind of stunts for years, and that Joiner will be as childish as possible in an attempt to ruin other organisers.
I would say Joiner has about a month to explain to people in clear and precise English (I know, he's not capable) what exactly is going to be at DSTL before people lose complete interest. People don't want cheap 80s school discos. They want what they've been promised, and right now they see no sign of getting any of it.