I don't think Jose was at all at fault for Salah flopping at Chelsea (he was somewhat at fault for De Bruyne imo) but he did only play him 11 times in all competitions so he was going to leave if Mou stayed regardless.
Anyhow, if anyone remembers Salah's games from back in 2014 or whatever you'll remember that he was fucking shit.
Jose Joins Chavs: Aug 13
Signed Salah: Jan 14 - 19 apps (13 EPL)
Loan Florentina: Jan 15
Loan Roma: Aug 15
Jose left: Dec 15
Sold: Aug 16