There is no way to combine a revenue and redemption ticket. That said, if ICN-XMN is a revenue ticket, I am guessing it is not even an AF/KL ticket since they don't sell that route on their own stock? In general, you cannot combine two separate tickets into one. They will always be separate. So even if you manage to get your bags interlined across two different itineraries (AF/KL usually do this for their own flights, and pre-pandemic usually worked for Skyteam partners too), the tickets will still be separate. This means that if the incoming flight is late, you will lose the flights on the second ticket.

Is the YYZ-CDG-ICN itinerary something you must absolutely fly? There's probably better way to get to XMN even with FB redemptions.

EDIT: As a thought, why not fly into one of the larger airports in China (PVG, PEK, etc.)? You will probably have a lot more options to XMN in that case than trying from ICN.