Ok that explains it,The bearing in the converter is damaged.I'd take it back to BTP and have them cut it open and repair it.
So how does a brand new converter that has 0 miles or use on it get a damaged bearing? My guess it was put together wrong or something was misaligned when they welded it up. Sucks.
The problem is that the turbine wheel accidentally got welded to the cover during the welding process on the OD. Make sure you check it when it returns.