If MCAS was ‘just’ to get a common type certificate Boeing would have bit that bullet by now and the Max would be flying. No one goes $9 billion in the hole to avoid a training bill.
The only plausible explanation for the time it has taken to fix this is that the aerodynamics without MCAS are fundamentally flawed, likely because the engines are to far forward and to high on the wing.
The JATR and EASA both want to see the unaugmented aerodynamics. If after a year they have not seen them, or have seen them and won’t accept them, the Max is likely not certifiable. The Canadians have pretty much publically called Boeing bluff (‘if it’s OK without MCAS, certify it without MCAS’).
The political pressure to certify the Max is immense. The technical case not to must be compelling.