Yes they do in this instance. New broly is canon, as is the saiyan base form power up that broly has. His power comes from the great ape power or some shit. Someone else can explain it better.
Leads me to think they may make ssj4 canon in some way if the tails return.
Movie is available in the usual places online with either Japanese or English dialogue with subtitles. Good quality.
edit: So, they ret-conned a fair amount of movies (3 or 4) -- I know they weren't canon, thought it was an interesting way of them doing things. Overall, pretty damned good movie. I would say this and Dragon Fist movie were the best.