Possible, though more likely they've all been raised as Death Knights by now.
However, you have inspired me to test another plausible interaction for a different spec...
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Which unfortunately did not work.
Once upon a time, there was a special scenario which occurred if you brought the Corrupted Ashbringer from Naxx40 into the Scarlet Monastery. All of the Crusaders would be friendly to you, and a scene would play out with Highlord Mograine. Unfortunately, this was lost when those instances were revamped, and although the principle NPCs are no longer present, I was hoping the presence of Ashbringer would do something, but sadly, it does not. There are still a few other places I could test, those areas familiar to Tirion, but I doubt they put much work into special interactions in obscure areas of the old world, as you would have no other reason to visit them.