Sorry to hear that. I'm worried I may have blown the seals in mine as well. It's expensive to rebuild the cartridge units, but I'll do it if I have to. It sounds like you've done everything you can short of the rebuild; I'd hate to see you quit now.
New Ride -- 2015 Z06 2LZ (stock) -- Journal
Old Ride -- 2012 Camaro 2LT/RS (647 RWHP & 726 RWTQ) -- Build Thread