it's... really hard to say. From what we know, mixed with a bit of imagination, the UA may be an artefact of a past era (imagine that, an artefact being an artefact) from the thargoid war some 300 years ago.
The thargoids could be entirely responsible for Antares & SS1 but that doesnt nessicarily imply Antares or SS1 had a UA on board.
The UA and the misjumps could be two separate things that both point to Thargoids.
It would be really cool if the Thargoids showed up for the wedding. Just sayin. Not being manipulated by anyone, just being all Thargoid- like and aggressive.
Thargoid 1: "This punch tastes worse than Klaxian thorax wine! <spits on floor/>"
Thargoid 2: "They could have at least served some of that Hutton Orbital crap! In a proper mug! <crushes glass of wine/>"
Thargoid 1: "That's the final
straw! I've had enough of this secret peace nonsense! Stuck on Quy, not allowed out, not even to go on a nice little fishing trip to Merlin. <looksDowncast/> Accused of being the pawns of INRA, or the pawns of the Dark Wheel, or some other lame pinkskin 'secret' organisation or 'Power'. Time to show them who really has the claws around here! You take the Emperor, the Federation one looks very appetizing in that business suit, leave her to me. What's her name again? I always like to know at least the name of my prey before devouring it."
Thargoid 2: "Dammit! Who invited the Oresrians? Don't they know there is enough bloody confusion about who we are already? And not a single appetizing morsel from the Alliance? And look - look over there - they've even invited that Senator Wager thing! [distant howl of anger - 'That's Wagar - Senator Wagar I'll have you know!'] "
Thargoid 1: "Did you hear that? The Emperor was just telling the Federation thing that we are just going to be another so-called 'Power'? P--s on that I say! I'm not going to spend the rest of my life space-trucking INRA videotapes from Polaris to Soontill for something called 'merits'! You think they could at least have had 'demerits ' or something for nasty alien races like us! What sort of design is that? Crush them now!"