I'm pretty sure the spit tactic would work, since Broly's only smart enough to put up a Ki shield if it's a YUGE Ki blast. If by some miracle he does choose to dodge the spit, he wrecks. He ought to be comparable to MSSJ Goku (Boo), whereas even Pre-Majin SSJ Vegeta wouldn't take long to dispose of Dabura in his own words.