Dual citizen passed away abroad, how to stop benefits?

My grandmother has dual citizenship and has lived with us, she took a trip abroad and passed away in her "home" country earlier this year. Now I don't know what to do - service canada, CRA, etc all need a death certificate to stop her benefits, BUT I cannot obtain that due to privacy laws in the other country. I would be required to travel over there and show up in person to obtain documentation, they won't even divulge how she died. This is not an option, I can't afford to take time off work, I don't have a valid passport, and I'm unwilling to risk my health with travel during the pandemic. According to the service Canada website it may take several months for the other country to share information about the death - clearly that has not happened yet, and meanwhile the government keeps depositing money.

The situation gets even more messy. I'm on a three-way joint account with her (her wish in case something happens to her), and I'm worried about the tax/legal implications of that overpayment. I know it will have to be paid back, but what about penalties? I'm more fearful of having the account frozen and my money getting taken hostage as well, worse yet criminal prosecution if someone misreads the situation and cries theft/fraud. To my knowledge she had no will, nobody has PoA, she also does not own any other assets apart from what she gets from OAS/CPP - most of that she would "pay" (via verbal agreement) me and my mom for housing and to take care of her, and also to just help us out since my mom lost her job and has health issues, while I have student debt.