Well, she's the understudy, there are no guarantees. And no precedent to do so.
Nothing against Jackie Burns, but a lot of Idina fans would be pissed if that's the show they had tickets to attend.
If we're not having fun, then why are we doing it?
These are DISCUSSION boards, not mutual admiration boards. Discussion only occurs when we are willing to hear what others are thinking, regardless of whether it is alignment to our own thoughts.