Thank you for the heads up - I will do my due dilligence and try and get as much backup documentation as proof of not being married.There was a case here just a few days ago of someone who'd had great difficulty getting the necessary docs for a Canadian to marry in Kenya - had taken months and it wasn't successful. I can't comment on that but have periodically heard that it is one of the more difficult places - they don't like the (minimal) documentation for 'proof of not being married' that Canada can provide.
So: my suggestion would be to either have back-up plan of wedding in Canada afterwards, or somewhere else before (why not Hungary, I believe straightforward documentation-wise). If you do it before, you can either have a post-wedding party or a religious ceremony with no civil aspect (if allowed) or a 'blessing' ceremony (in some religions anyway this is not controversial).
Otherwise no particular issues with your plans. Warning that the work permit can take some time and may even come same time or after the PR status.
Quick question - When applying for both in-land sponsorship & open work permit at the same time - is it true that the spouse can start working as soon as the application is submitted for open work permit and is in process?