Need help with vibration!!

The whole thing has to be balanced together in the same manner. It's ALL one rotating assy & can't be separated into 2 halves. The flywhell is going to have an effect on the front part of the assembly as well as the back part. Same for the balancer. You can't mix an externally balanced damper with an internally balanced flywheel(un-modified) & rotating assembly.
I don't know what your machinist did in his balancing process, so it's hard to be able to tell you what to do now. If it were me I'd have it all redone & ditch the external balancer if you still intend on an internal balanced assembly. I'd probably use a different machinist for the job since his work so far has me skeptical of his knowledge.
I hope this helps. Good luck.