If they really need 777 Skippers they should ensure you are line-checked Hasta Pronto. . . . but, if you are not ( & they can fly you for free in the LHS, accompanied I am led to believe by a "retired" TC in the RHS. . well, he is "cheap", but Happy, as he is making some post-retiral bucks & ) you. . . are FREE , so you are in any case "earning" for them big-time.
I sincerely hope all the stories are exaggerated, for sure on the 737 they are not . . maybe (?) the 777 is better.
I hope you will come back to us & let us know how quickly (or otherwise) you were on the payroll, thereby enabling others to make a considered decision.