And the choosing to ignore Ford as THE Sam Evans in the DVD would be pretty public too. I can only surmise that there was a lot of animosity after the marriage broke up, which isn't surprising, what surprises me is that it would apparently continue for so very long.
Mark Allen went on the first location shoot to Newport -- although only one shot was ever seen onscreen due to his rapid recasting. But yeah, that's almost certainly the reason he was chose to represent Sam Evans, as David Ford never actually made it out on location.