That is true,
I believe the names of registered poll watchers is a matter of public record.
The old man wasn't really interested in his name just who he worked for. The watcher had said that he was working for one of the parties but that's all he could say.
The poll workers defended him and said people working inside the polling place weren't allowed to identify themselves by party.
Personally I think the old guy is right. Watchers should wear a tag saying who they are and who they work for.