The Lego Star Wars series is treated as a licensed property and as such, totally non-canon.
Although it and the Family Guy specials can be found on the official Star Wars site, it is important to stress that the studio does not consider it in any way canonical, indeed there are multiple instances (Yoda meets the droids before ESB, for example) that flatly contradict the events of the films.
Michael Price, senior writer for all six of the recent animated features stated this in an interview for Club Jade;
Michael: That is actually incredibly freeing — that and the understanding that these LEGO Star Wars shows are most definitely NOT
CANON. So we were free to make up an imaginary back story for Han
Solo in The Padawan Menace and, in this show, invent entire events
that never took place – including the kind of awkward and tense
reunion (or, I guess, first ever meeting) of Darth Vader and his
“step-brother” Darth Maul. And the fact that both LEGO and Lucasfilm
have been supportive of my narrative sidetracks, the mixing and
matching characters and places from the various films, and our
satirical swipes at some of the Star Wars sacred cows just has made
the whole experience very fun.