In the Thieves guild quest, "Scoundrel's folly" I'm supposed to shadow Gulum-Ei but as soon as I leave the inn he seems to disappear and the map marker is pointing to a place outside of Solitude. I went there but there was nothing.
I also went inside of the East Empire trading company and he wasn't there, so I continued to the cave where then my mission objective updated and said "confront Gulum-Ei" but once again, I searched the cave and couldn't find him...

Any one else experiencing this? Any way to get around this?

I'm on the xbox 360.

You have to swim once you get far enough in that cave. There's a secret passage that can only be accessed by swimming. Once you get there he should be all the way at the end.

Yes I know. I went in there and that's when my quest updated but I still cant fine that stupid little Argonian. :/

I think I had the same problem when I did this quest. When your at the part where it says confront him there should be a couple bandit camps as you make your way through it. Search the right side of one of those camps and you should find a passage leading to the argonian. Its really easy to miss and took me a while to find this.

This is a common glitch. I′ve even registered at the official forums to see if there was a solution but there isn′t at the moment.

Even IGN went through this:

"There is a glitch where Gulum may not show up, so be sure to save just before you enter the grotto. Upon leaving the Grotto the tracking marker leads you right back to the warehouse and would lead you to think that Golom is behind a very solid mountain of stone, fully arresting the progression of this questline. More information will follow shortly."

http://www.ign.com/wikis/the-elder-scrolls-5-skyrim/Scoundrel%27s_Folly

After a few hours of this bug (clearing the grotto and not finding Gulum) and trying the graphics glitch solution (it did not work)... I went back to the Winking Skeever hired a room for around 24 hours... went back to the grotto ... and when I got to the clearing with the 3 switches Gulum was there.

tatlin