They knew when they sent the request we were in another province, all part of the game. Chase, chase. Dangle the carrot.Pull carrot away.
This does not make much sense - submitting the proper marriage documentation should have been done with the original application. They're not pulling your chain, they've given you a chance to correct the original documentation gap. Chinese requirements on how/where to get notarization done is not IRCC's 'fault.'
At any rate - on a separate point, and with concrete advice, and a way to channel your energy - you should apply for a TRV for your spouse.
If it gets approved - then you have a way to travel to Canada together whatever happens.
If it does not - and any issue arises with your sponsorship app - you have at least
some additional support for your intent to go to Canada. (Again objectively one aspect of your original app was that neither you nor your spouse had travelled to Canada at all in the years before your app).
Applying will not have a negative impact on your sponsorship app. If asked at any point about this, simple (truthful) answer is you had originally anticipated PR app to go through more quickly. This may be a bit late to help but worth a try - in my view.
(Granted the weak part of this is that since your spouse has now resigned from employment she has fewer ties to home country and higher probability of refusal)