The rest of the story ....
Here's what I didn't know at original post time:
They did cook the BB xfmr (that's why the development of the question about potential for a phase shift that I posted). Seems as tho the board needed 2 hots, neutral and ground because it's basically nothing but a big multiwire ckt and needs the neutral. It came from factory with these 4 tails attached and labeled. The sign guy on top of the ladder told our guy 240 volts ... period. No mention of the neutral and our guy didn't go up and look or question it (strike one). So they hooked up a BB, did not pass the system neutral through (strike two) and fused the primary using the proper fuse size for the secondary (strike three). Guess what smoked. We got lucky it was the xfmr, not the board.
Thanks for the help and we got the guys straight. Nice video board.