Yes, it all jibes with the backstory for Barnabas that Art Wallace came up with.
[spoiler]I've always thought it was a brilliant stroke on the writers' parts to have Joshua supplant the truth with his own version of events and to have them laid down as the "facts". But even at that it doesn't explain away why Barnabas was so off about his own life. Though, of course, DC believed the audience would have completely forgotten about what was said about the events of the past, and probably even who said what, so he thought he could easily get away with the radical changes made in the 1795/96 storyline.
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