If the crank assembly is like the Qingqi, then they won't be able to do it. The chances are that it is of the type that comes with one-piece non-detachable conrods. That is the crankshaft and conrod has ball or roller bearings and the rod is assembled on a press and supplied as one piece. The balancing machine could not cope with a loose conrod.
Dynamic balancing can only be done on engines where the rods are two-piece with plain bearings, and the crank is one-piece like a car and the rods can be taken off the crank.

In this exploded view you can see what I mean, the whole thing is pressed together under enormous pressure: