If you don't mind me asking, what was the price you tentatively agreed for the jersey?
If you ask me, Ben is well within his rights to get whatever he wants for it. A signed jumper like that would clear the $1000 mark comfortably, particularly if he auctioned it off at a key event such as a Grand Final function or the Richmond B&F. I know people are cynics, but Ben has recently auctioned a heap of gear for charity, so you never know.
Whatever the reason, it's laughable that you would consider to stop collecting your favourite player because he wouldn't give you a match worn guernsey, despite any word or mouth agreements (which aren't worth sh!t, particularly when you're talking about exclusive memorabilia).