Probably I'm just overthinking it but it is quite curious Hajrudin referred to giants with a Logia as they were extremely rare, perhaps even unprecedented. It also seems giant DF users in general are not common at all in the OP world, Loki is the only one we know of
If BB is a Buccaneer, maybe he was able to eat two DFs because he was (in part) a giant with a Logia. It is plausible not even the gorosei in 800 years ever got their eyes on a giant with a logia that tried to eat 2 DFs, Jarul and Jorul are like 300 years old (and DFless btw) and they would have told Hajrudin if they saw one