I am unable to find the answers calling Canada Pension customer service or Social Security customer service. Appreciate your help if you know the answers.
In case you've not seen them, these links may help:
Best place to get an accurate answers is IRS pub 915 on taxation of SS benefits which is available at irs.gov/ forms.
I will be in the same situation (different country, CH).
Note that you can "only" lose up to 50% of your foreign pension.