I am not in your area, but it can be done. Have him complete PADI elearning online, that will save about 5 hours right there. It can be a very effective learning tool. For confined water and ow training dives find a facility that has its own inhouse pool so that scheduling pool time is no issue. OW training dives take 2 days as standards only allow no more than 3 training dives in a day.. On day 1 do confined water (pool) 1-2-3, after module 3 is completed he only needs to do ow training dive #2, if he has documentation of his previous Discover Scuba Diving OW experience as that can count for dive 1. No documentation of discover scuba diving, then do dive #1 and #2.
Now on day 2 he completes module 4 and 5 confined water and in the afternoon ow training dives 3 and 4..He has now completed all requirements for ow certification.
Kind of quick, but can be done , I do not endorse such a schedule for most.
..Can be usually be done if on private basis and he picks thing up easily.
It will cost $$$ as it is private basis and on a holiday..Here in NY at facility I teach out of it would cost $550 for confined water work and additional $1100 for ow dives on a nearby boat as there is no beach access nearby (less than 20 minutes away from pool) to meet the time frame. Boat alone is $700 in that fee..all 4 training dives together normally runs $239 with gear rentals included,but that is in a group schedule. To meet desired time frame and pay instr enough as it is 1 student figure on $400..total comes to $1,100. boat and instr for the 4 training dives alone.. can be alot less if boat is not required and you have beach access in your area.