US flying school incl. conversions etc would not make the final bill that different.
Working in US is nearly impossible, unless he has US passport/work permit.
Deciding against military aviation in my opinion is probably not really a choice you do, as competition is fierce.
The real cost if you are going to have a fair chance of getting a job would probably be close to £90 - £100K, as in todays market you would need to either get into an airline scheme with integrated school, or do modular and pay your own type rating in the end, example with Ryanair.
And let's be clear, pay is not what many people imagine it is. So before deciding against military aviation, where all training is "free", he should do a bit research, as there are currently thousands of pilots with few hundred hours, "fully qualified", but unable to get any jobs!
Search forums here for various cadet schemes, they are far and few in-between, but would give better odds and tips how to invest your money!
I personally have no regrets for doing this, but I would not recommend anybody this path, specially if you need to borrow money on your parents house. Expect the worst, and hope for the best! Good luck!