together with some of the best political leaders of his day

1) Tom was wrong with some of the best political leaders of his day.
2) Tom was wrong alongside some of the best political leaders of his day.
3) Tom was wrong alongside with some of the best political leaders of his day.
4) Tom was wrong together with some of the best political leaders of his day.

5) Tom was wrong following some of the best political leaders of his day.

Which are correct?

'5' doesn't mean exactly the same thing as the others. In the others they were all wrong, but there is no implication that Tom followed them. He might have or he might not have.

I'm not sure what the writer is trying to say. Apparently, Tom is wrong about something, and some of the best political leaders of the day are also wrong about that.

I wouldn't say someone was wrong with/alongside/together with another.

Why not make it simple by saying both A and B were wrong or A was wrong, followed by B?

Thank you both very much,

Yes, that is the intended meaning.

Abe is wrong. Bob is wrong. Clive is wrong. They are all wrong. They just won't admit it.

Somewhat closer to the original, you could say Abe is wrong, and Bob is also wrong.