I went ahead and adapted the by Jeremy_Foran’s nodejs logic (with some pretty awful groovy) into a device handler: https://github.com/kennelbound-smartthings/kevo-unofficial
You have to specify username, password, and lockid in the settings, it logs into mykevo for literally every command (no token or session reuse), and doesn’t wait long enough to verify the lock status (so after locking, unlocking the status is almost always wrong). But it works and you can lock/ unlock directly.
If you want to not allow for unlocking, you can change the capabilities appropriately. Let me know if you have any trouble.