Could it not happen during the events of the movie? Why does it have to be a past event? Remember it was the 5th anniversary of the Alliance that motivated the Drakh to attack Earth last time. Perhaps after the events of Crusade, the Drakh resources are not so extensive/expendable and so they motivate the Centauri into attacking (maybe with pod powered ships) on the 10th anniversary. I can't remember... but would anything in the Centauri Prime trilogy forbid that event taking place?
Not as such, though of course, for obvious "real-world" reasons, there's nothing mentioned in the final Bester novel of the Centauri NYC attacks (set right after the end of
Crusade, in 2271, and presumably roughly concurrent with the events of
The Lost Tales), nor of Prince Regent Vintari. Nor in the last Centauri Prime novel, set in 2278.
Though JMS was/is clearly aware of their existence (having personally scenarized them for Greg Keyes and Peter David), and probably structured the new series so that the episodes work around them without too many contradictions. I don't see him going out of his way to disrupt any of this, owing to his inclusive attitude towards the novels, barring, of course, different storytelling stances that Joe might decide to adopt
vis-à-vis the new show.
From what I recall of the Centauri Trilogy in particular, the action focused around Londo and Vir within the palace itself, with Prime Minister Durla the Drakh's main ally apart from Mollari...but then again, nothing was ever established one way or another concerning Cartagia's "wild oats," and potential offspring, so there probably aren't going to be very many discrepancies on that front, either.
It all depends on the specifics.
