You should not have a problem killing those last two bosses

Jergosh and Bazzalan: Follow the Yellow route until you reach the fork (see map). From here on you can decide if you want twelve sky2 Gold to go for Bazzalan or Jergosh first. It's up to you. If you managed to Kill Taragaman, you shouldn't have a problem killing those last two bosses.

The only difference is that they have guards. So use sap and polymorph on them and kill the boss first, quickly. If you don't have either, you can use Warlock pet or Hunter pet to off tank an add, and kill the other add quickly while the warrior is tanking the named.

Just make sure everybody follows the same plan, and attacks the same target for maxium efficiency.

Jergosh the Invoker almost always drops a decent green item, in spite of Bazzalan, who rarely drops anything of value. Once they are both dead, you can either use Hearthstone or clear your way back to the entrance, it's up to you.

Congratulations on finishing your first instance, now is the time to go turn in your quests and get your well earned rewards! It is the first time to gain rewards of completing instance. Enjoy your world and your own WoW currency!