The logic of the scene has always bothered me. Lando is the choice to go with Luke to track down a Sith assassin? And when Luke gives up to go train the next generation of Jedi, Lando just stays there? For ~30 years? Not continuing to track down the assassin, nor continuing his search for his daughter… just decides to chill the the desert, and wait 30 of the 42 years for the festival?
The randomness of him showing up after his best friend’s widow dies is less than him living in the desert for 30 years, but that’s just me.
I feel compelled to point out that in earlier cuts, the reason Lando was the person who went with Luke is because the First Order (or, rather, what they’d later find out was the First Order) had taken Lando’s daughter; Pasana is where the trail went cold, and so that’s where he stayed, trying to find more leads and find peace for the next ten or so years, and joining the local community. This is retained in the novelization and visual dictionary.
As always, I’ll maintain that most of the problems in this movie have to do with JJ Abrams extremely attention-deficit editing style.