Jay did pullups, he even has a few vids talking where he mentions how pull ups are one of the best back exercises to do.
I think he mentions it in his "does Jay hate ronnie" video
Yes,I am 250 right now,and I do 7,8 with bodyweight,and can do a single to the chin with a 65lbs dumbbell.
When I was 285 I was also doubt 7,8 bodyweight and 45 lbs plate for two.
IMO nothing comes close to widening the lats than pullups.
I do not how they can skip doing it.
Probably because they can only do one or two reps when they try,and they just quit.
But pullup strength develops quickly,if you can dedicate 10 workouts to chins you will go from 1-2 to 6-7 and then so on.