Am I right in thinking that the bond was originally secured on the value of the stadium?
Yes that is correct.
So would a rise in the value of the stadium and associated businesses help with any future refinancing?
It wouldn't hurt, it would offer some help. But the main thing at the moment is that the cashflow of the 'business' (have to view it as business rather than a sport when looking at the bond etc) looks a bit unsustainable because of having to pay the interest on the bond. That's why it would be handy if the value of the next bond could be reduced, to reduce the interest payments.