I don't think that the crews nationality or indeed their passport holding makes any relevance to their flying standards / company standards.
They are a UK G- registered airline and like all other UK registered airlines are subject to the same level of regulation from the CAA as anyone else. It is a common fact that MK buy B747's and use them for spares. The Air Gabon at CDG that was written off and the Air Madagascar sitting in Chatereux are two that come to mind. It makes financial sense as long the the parts are certified and logged as per the company MEL and maintenance faciliy (MK's is EASA 145 approved at Filton).
Since the Halifax crash MK has had to bring itself into line and pull its socks up, I think they have done this, if they are changing their brand then good luck to them.
Kind Regards
Vince