You still didn't help me, but anyways..
I found a glitch, its in the Rock Bottom level
when you go to the part where there is 2 of
those sleeping robot guys, there should be a
building near them, if you go to the right side
of the building (make sure you don't fall off the cliff)
and go under that bar thingy (whatever you call it)
and if you keep jumping you should be able to
be inside the building, but the robot guys can still see you.
Just thought it would be something to share.