I have Drazic and Rodan and when I went to talk to Za'ant, he turned hostile. I did not two any Umpani or
T'Rang quests that would hostile the others but it Za'ant knows that my party was working
for the Umpani in addition to the T'Rang. I paid off the bartender in Arnika already.

Any suggestions?

Go to Yamir, if he is hostile too badluck, ifnot talk to him and get that letter. Give it to Zant, do not speak to him. That should work.

I got the letter from Yamir, but couldn't get Z'Ant to accept it. The moment I was in view he turned hostile. I guess I killed one too many T'rang. I was never able to complete the alliance. It didn't seem to have an adverse affect to finishing the game.

Before speaking with Zant, remove the alliance letter from your inventory, and click it on Zant to give it to him-- don't use the usual speak/trade/give sequence.

This may or maynot help: Zant sometimes seems to hostile for no apparent reason.

Oru