As for voting under duress, it’s also a concern with mail in ballots and voting by phone. It can be worse with online in the same way that scams are easier online.

I know someone who voted by phone this recent election in my home province, and they were eligible to do so because of sudden health issues. The phone call included multiple people who verified their information, took down the vote, and then verified the vote. I imagine it would get flagged if there was any discrepancy