This private jet business is, I suspect, being deliberately misleading. Once they had decided to get him back in principle, the practicalities of the transport need to be thought through. I don't know what the costs of the alternatives are - eg some military jet perhaps - and maybe they wanted or were required to have a level of security which was not compatable with taking him using scheduled planes with possible interchanges and other countries to worry about. Whatever the calculation was, I doubt very much whether anyone said "and we need the plane to be luxurious".