Perhaps it's related to the patriotic resurgence routines. Sort of a "sunk cost fallacy" where loss of cities causes the government to double down on resistance rather than quitting. Giving up pieces of the Motherland is bad and all that. Could just be an editing error, lord knows WW1G has enough of those.[This does not make sense to me, why would occupying Russian cities increase possibility of the rejection? Shouldn't it be the opposite?]
Mutinies can be brutal but losing the Ottoman Empire should not prove decisive. On the other hand, knocking out Romania can really hurt Russia.
-C