Probably Kurt Dams in Veerle, near Tessenderlo.
I've seen twice a crack in the bb-lug before. Lateral flex is normal for Alan, certainly with strong riders and bigger frames. It depends how much flex ...
I know a lot of people ridin' with a crack in a lug, most of the time the head-lug. My lady rides that way for years, on a lady-frame, no uppertube! I myself got one with a crack in the seat-lug. It has never been a problem.
Aberto Falconi, the AL from Alan, seems to have said there are no riscs ridin' with a crack. The glue is more important, so never weld a crack!