The earlier answer I posted is incorrect. Below is a revised response from CRA.
I was not satisfied with the earlier approach because it doesn't capture stock accumlations from previous years. I called CRA again at their inquiries line (1-800-959-8281). The agent I spoke with gave the same response as described above. However, she felt uncertain about this and said she would get someone to get back to me after looking at it more deeply.
A couple of days later another agent called me back. This agent sounded very confident in saying that the treatment should be as follows:
1. Cost amount is the total adjusted cost base (ACB) of all stock grants from 2018 and 2. Income should only be for things like dividends/distributions, not for the awarded stock amount
3. gain/loss on disposition is the capital gain/loss on selling the stock, based on the ACB.
This is also consistent with what a colleague was told by an accountant from a tax preparation company.
I had already filed my taxes based on the earlier advice. She said it would be okay to use ReFile to revise it. (
https://www.canada.ca/en/revenue-agency/services/e-services/e-services-businesses/refile-online-t1-a...)
She agreed that the FAQ (
https://www.canada.ca/en/revenue-agency/services/tax/international-non-residents/information-been-mo...) was not clear enough about this and there were proposals put forth to improve it. However, changing the FAQ is not straightforward because the terminology in there must adhere to the Tax Act, which doesn't have definitions for things like foreign restricted stock units.
She suggested using the "Report a problem or mistake on this page" at the bottom of the FAQ to let CRA know that this is a concern. I'll do this, and in order to let CRA know how widespread this situation is, I encourage others to also do so.
