This is all pending on = this means that the out come of the game will determine who the celebration will be for.

Team A beat Team B. = everyone and/or the odds of Team A beating or winning over Team B will be big so that a celebration can happen. Also this is assuring that Team A is the best by far.

Now lets put it together. And the sentence can now read:

The outcome of the game is determined on Team A to beat Team B.

or in more simpler talk it will read:

The final score will show that Team A beats Team B.

So go celebrate with Team A as planned.

“This all depends on Team A beating Team B.”

or

“This is all depending on Team A beating Team B.”

To use “pending” you’d have to say something like:

“The question of which team wins is still pending.”