Administrators are not here to win friends. Their sole purpose is to maximise the return to creditors. If maximising that return to creditors involves an equity injection and ownership change through VCs, that's exactly what they will do. I don't know that the unions will have much say in this and they are hardly likely to walk away from something if that keeps a percentage of staff at work.
Unions refusing a deal and forcing everyone out of work does not seem an option.
Aside from that, no one really knows what the 2 VCs will come up with as a firm offer - it may be so low that the administrators need to re think where this is all headed.
Almost in the too hard basket.