How to make this SCBA tank work

A bud took the plunge in the deep end of the pool and purchased a very nice PCP. As beginner's luck would have it, he got a hook up on a GREAT 45 minute tank. As shown, it has the Firefighter quick disconnect and a CGA347 thread on the valve. I'm not sure how to advise him on getting the correct fill adapter with that valve. I am going to hook him up with a China classic hand tight SCBA CGA347 fill adapter if it works
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Question: Does he need to replace his current valve or will my CGA347 fill station work as is? Is there a either/or check valve with his setup?
 
Given that he wants an inexpensive valve, my recommendation is to remove that CGA valve and replace it with this one. Fireman's tanks have a 7/8-14 thread so opt for the valve with that thread, not an M18*1.5 which fits most Chinese and European CE certified tanks.

HPAT PCP Scuba Diving Valve Air Filling Station Recharge Adapter 40mpa 24'' High Pressure Hose M18x1.5 Male|Paintball Accessories| - AliExpress

if he keeps the CGA 347 valve and buys a fill assembly, he'll pay almost as much as this valve costs. It provides better ergonomics than the existing valve and added fill assembly and includes everything he needs to fill PCPs.
 
There was a thread on this style awhile back: https://www.airgunnation.com/topic/need-advice-on-scott-scba-quick-connect/ and these type of scba valves are a little problematic due to a check valve on the threaded inlet. The conclusion was that the most economical method to make this scba compatible with a typical cga347 fill station is to replace the scba valve with one that does not have the quick connect fitting such as one of these: https://www.ebay.com/itm/114731253081?hash=item1ab683fd59:g:eek:DAAAOSw4BVgUvMN