Luring people into doubting elections and democratic processes is a staple practice of fascist politics.
It's a win/win move for them. It casts doubt on democratic institutions and processes which weakens them and it, if successful, also may gain them a couple seats.
The public needs to start pushing back against behaviour like this. This was not even a super close election; there are very clear seat count differences between the incumbent and opposition parties.
Should almost be against the law to sow disent like this in our elections without proof.
That mail in ballot that was rejected because elections canada had the put the wrong postal code on it or whatever it was, sure, you at least have proof and a legitimate concern.
Baseless accusations though, slap them with increasing fines or something.
Edit: especially from any candidate involved in the election