Since this is illegal in most western democracies, I would have told the police if I had witnessed this.

In fact, in the UK the polling staff are told that they need to assess the competence of the person voting ahead of time and that the person voting must do so alone and without duress, else they should not permit the vote to be accepted.

https://www.electoralcommission.org.uk/voting-and-elections/...

> You’ll talk to voters as they arrive and make sure they know what to do.

https://www.electoralcommission.org.uk/sites/default/files/p...

> The role of polling station staff is to ensure that voters are able to cast their vote in secret, free from influence and in a calm atmosphere.