Sir Menzies Campbell can protest all he likes: it has nothing to do with him, and he is in any case going to be removed as part of the whole process. This Eustonite pseudo-Labour Government is determined to bring in, not only Orange Book Lib Dems, but also Jacksonite pseudo-Tories such as now run the Conservative Party. After all, they are all really members of the same party anyway, the party that it is now impossible to vote against.
As for making non-MPs Ministers without giving them peerages, so that they will be members of the Government but not of Parliament, that will be yet another step down the ruinous Liberal road of "the separation of powers", on which see here.
We need new parties.