I just spoke with One More Cast, and I have to say that it is quite regrettable when things don't proceed as planned. We all have had plans that were foiled or just didn't work out as designed, predicted, or hoped for. I understand the frustration, and I share the regret.
It is statistically very unlikely (but not impossible) that those bass came with the load of baitfish. Our fishery biologists, including myself, are involved in handling these fish and loading all of the trucks, and the entire team is well-aware of the importance of quality control in this business.
It is more likely that these were introduced recently, as George makes a very good argument and provides great advise. We agree that the plan for now should be to sample the pond very thoroughly and report the findings.
My suggestion may be to electrofish during the early spring bass pre-spawning season to harvest as many existing largemouth bass as possible, then follow that with the introduction of adult high quality florida bass that are fin-clipped. The nuisance bass can continue to be harvested rod/reel and easily identified by lack of clipped fin.
I would like to thank One More Cast for not casting irrational blame on his fish supplier, and I hope that we can manage around this unfortunate circumstance.