The Serpent Temple is southeast of Ishad N'Ha...

Leave town and head east. ( keeping to the right ) When you get to the water, follow the shore line. ( Also to your right ) You'll come to a small wooden peir, get out and talk to 'Kol'. ( if you get tired of listening to him, just type 'Key' ) Unfortunately, you can not get in the front door, so you have to wander through the woods to your left.
As for the other questions...Scaban is lost..One option is to '
reset adventures ..( You keep your skills, level, role and loot, but lose any quest items and quild memberships. )
Another option is to kill Tevik Teporn and try the 'quick click trick', when you go back to talk to Onabe.....( Save before you enter town )... Click on the wizard before you enter the magic shop...After you enter and Onabe starts his greetings, click on another character and then back to your wizard. If your lucky he'll get confused and promote you twice...