Does bank draft (deposit) must come from buyers own' bank account?

from my experience yes it can come from another account but you should the pros who are doing the sale (bank, lawyer, brokerage etc.)

healsio wrote: ↑ The buyer is a foreigner located outside of Canada...

If no mortgage is needed to close, can the money come from another person's bank account in Canada?

The draft deposit can come from anyone. The realtor receiving the deposit on behalf of the brokerage has to FINTRAC the person who issues the deposit and specify the relationship between this individual and the Buyer. The Buyer obviously needs to be FINTRACd as well.