I got the slide off. I think it was stuck because the recoil spring was backwards. I put a ton of CLP on it, and let it sit for about 6 hours, though in reflection I'm not sure this helped. Then I used a small rubber mallet to get it loosened.
When I bought my thunder I watched a Youtube video about disassembly and the person doing it said to be sure to slide the tight end of the spring over the barrel. There is no tight end on the spring in my pistol which is brand new. Perhaps what you experienced caused them to rethink that situation. Mine seems to function fine but like others, I need that bit of wiggling when trying to get the slide off the barrel.I got the slide off. I think it was stuck because the recoil spring was backwards. I put a ton of CLP on it, and let it sit for about 6 hours, though in reflection I'm not sure this helped. Then I used a small rubber mallet to get it loosened.