Bingowings said:

The problem now is the nature of his dialogue, if he is truly trying to save the galaxy from a Sith Lord he would be trying to justify his Alliance to defuse the situation.

I don't know if some of the exposition from the earlier scene where Obi-Wan has been captured could be moved here so he doesn't seem like he's bitching for a fight.

Constructing a line like "I was not deceiving you, the Republic is under Sith control, The Alliance is the only hope of restoring peace" may not be possible but with the huge number of Christopher Lee films to pull from it might be possible to assemble something similar.

Well, honestly we know why their fighting, the rest is just trash talk. The chatter in the fight could be cut and that should do it.