Have you any videos?
I ask because I roughly that strong but I could not do 435lbs
If the 315 is an all-out max set then there is no way someone who gets 10 reps of that can bench 435x1. I would put their 1RM in that case at around 400 at most since you're going to lose at least one rep for every 10 pounds you add.
If the 315x10 was preceded by other taxing sets then I could see 435 perhaps.
I always get a kick out of all the jackasses at the gym who'll do 225x8 or so with their platonic lifting parter rowing the last four reps off their chest and afterwards be all "bro I could totally max 400 if I was warmed up / trained PLing"