I don't get the point D2M is trying to make then. In Spain, you can keep a "replacement" manager for 2 weeks - after that, you either have to sign him or move on.
At the time (and even still, really), it was the only thing to do. Season was already lost and all they need to do is ride it out, get top-3 and re-tool over the summer.
Noone seriously ever thought Solari was a long-term solution, but again, Spanish rules say you must sign him after the 2 weeks.
As for the next manager, I'd say:
Mou 50%
Zidane 30%
Poch 20%
Either will do fine for Madrid, as long as they get the funds in the summer.
Seeing as how Perez hasn't brought in a big name in since 2014, I'm guessing some splashes will be made.