I am having the same issue as well and it is in fact a bug. I loaded three save files:
One was my current file where the planet was completed. I went to Dantooine to trigger Lena. I then went to Tatooine and talked to the Chzerka(SP?) chick and FPed her to tell me about Griff and the Sand People. I then went to the sand people to set him free, I did, but he was not there at all.
Second save file I loaded was one where I JUST killed the Kraat for the pearl. I returned to Dantooine, did the same above, and Griff was NOT there still.
Third one I loaded was one where I already talked to the Sand People agreeing to give them the water device. I went back to Dantooine (did the same thing in the first save), got the water device, and then asked for Griff. I went, opened the door, and Griff was there.
The difference? The first two saves that I loaded, I had already opened the door to where Griff was being held captive before starting the Griff Quest line. If at anytime you open that door PRIOR to talking to the Sand People asking to set him free, he will never show up. You need to make sure the door stays shut until the Sand People agree to set him free.
Well, they dont' say they will set him free, but you do get the line where they can't stand him, and we are able to let him out freely.
All these saves were made and loaded with V1.03 (I update all my games before I start playing).
I just can't figure out where in the Save Editor to trigger this so I can complete it.