Yeah, that works. Have any of the Legends comics or books ever filled in the lightsaber's backstory? Or at least said who the original owner was?
That one specifically? I don't think so. So far as I'm aware, nothing else in the EU really touched on anything from Droids, storywise, just a few sideways references in reference books, that kind of thing.
Not that this is unusual, the EU wasn't as interconnected as some seem to make out. Typically different projects only made bare minimum reference to others (see the narrative whiplash that was The Heir, Dark Empire and Academy trilogies taking place back-to-back, or the narrative & aesthetic disconnect between TotJ & KoTOR). And that's if they even did so at all; just as often they'd flat-out contradict them (I think there's like 5 versions of the "that bounty hunter on Ord Mantell" incident!)
There's been references to Droids in the new canon, but I'm honestly drawing a blank on what they are. I think a character was mentioned in a book.
There are also a couple references to the show in the Prequels
https://starwars.fandom.com/wiki/Star_Wars:_Droids:_The_Adventures_of_R2-D2_and_C-3PO#Continuity
The only one that comes to mind is a line in one of the reference books indicating the model of speeder bike used by both Ahsoka & Kanan at various times being designed by Thall Joben and the Zebulon Dak Speeder Corporation.
Of course that would mean the events of that arc (if they happened) would have to have occurred prior to the Clone Wars, which rather prelude's Artoo & Threepio's involvement, to say nothing of Boba Fett and the Empire.
And yeah, the Boonta Eve Podrace does seem to be a deliberate reference to the Boonta Speeder Race, though it seems a little odd considering 'Boonta' was a planet in the show, and 'Boonta Eve' seems to indicate it's a holiday. Not that it can't be both of course.
I guess that the show was also the first time a two-seater A-Wing showed up counts for something too?