I thought we are finally get some more updates since the last cliffhanger with the Dandelions, but it is still Wreck It Ralph and laugh for my own silliness. But I did watch the whole update and surprised with the intense level (comparing for normally Disney world) and especially that plot being revealed by King Candy which identified Player as another
Going by the wording of the Report there are at least two beings Luxu describes as a "virus".
The impostor "not chosen by the Master" among the "five" aka the Union Leaders which he states "represents" a virus and then in the next paragraph he mentions the virus undertaking a "reckless plot" to allow "the five" to escape into another worldline.
The first mentioned one can be either Blaine or Ventus but if I recall correctly Blaine's name was on the note detailing the new chosen leaders while Ven's wasn't.
So Blaine most likely was chosen to be a Union Leader, but he wasn't the one chosen to get the BoP, that is the thing off.
Question is does Luxu even know about this?
Ventus is apparently mentioned/detailed in the BoP as the "carrier" of "Darkness" but that can of course also be a muddy issue since we don't know if this "Darkness" being is actually telling the (full) truth there.
The second one however describes Player somewhat to a T, recklessly trying to save a group of people which includes their two closest friends.
On a side note though, "virus" can also apply to those Darkness-beings as well as Blaine, Ven and Player together as in 99,99% of cases a virus never consists of only a single cell.
I also believed this in your way after watching the update, and reading the report and also your explanation.
We can at least for now, be sure that Luxu has no idea about Player and what he/she had done, comparing with King Candy named Player as a virus. But with what we have seen so far with the Dandelion updates, Blaine has higher potential to be the virus more than Ventus due to whatever he had been pulling so far. Unless, a plot twist is waiting for us that flip the whole table and make either Blaine or Ventus end up as what Luxu mentioned in the report.
This feels to me, we have an "internal virus" and an "external virus" both messing around with the system that MoM has created.