Luxstar,
if these chaps already have FAA ATPL licences, why should they go back to CPL and not use their instrument rating. The CPL will also restrict the mass of aircraft which they are entitled to fly (and, for which, they may be already type-rated).
In their circumstances, a CPL would not be the way to go. I should also point out that there is more than one ground school provider for CPL(H).
Cheers
Whirls