Now that's an interesting question. I never thought about that personally. But this is how I see the combination:
The card says to basically spin again if you land on Miss. I always read that as for the "initial" attack (or for which attack would happen). So, if you spun and the first result was Miss, then you would spin again until you landed on something that wasn't Miss.
The Attack Fire Spin is specific in it's wording, and I don't think the X Accuracy card would change it. So, even if you landed on Miss while doing the Fire Spin spin's, you would still end the attack and count up the total.
Basically, I feel that the X Accuracy card takes effect at first. If you land on Miss while resolving the Fire Spin effect, the attack ends then. The card doesn't change the effect of the attack itself; just if you use it at first or not.
Does that make any sense?
Also, this isn't official. This is just how I see it (for now). It's a strange combination really that needs more clarification in the rules of the game. That's the one thing that I'm sad about the TFG in general.
Gibby