I imagine Dark Rangers more so seeing as they have pro Horde connections and maintain pro BE sentiments given Velonaras dialogue about seeing BEs as kin still.
And if other Horde races worked w and continue to work w the Dark Rangers that stayed behind I don’t see why BEs wouldn’t be sympathetic to them if anything more so on some level.
San’layn specifically less so you’re right I feel like but I feel like that isn’t as huge as a problem as it sounds. Given didn’t they recently conflate the meaning of Darkfallen to include both Dark Ranger undead types and San’layn. So all that’s really needed is for a small moment w San’layn imo to have them make sense somehow. Blood Elves entire recent history w the Horde has seen them build new authentic friendships and allies and in some cases w old enemies at that.