Can you point to a policy wording that says in economy? I’m guessing that is policy specific.

With a good policy , If you’ve bought trip insurance on a business class ticket, it should cover you on a business class ticket. At least the policy I linked to above. No doubt those policies are expensive.

Usually insurance replaces like for like.
cheapest way home might be by bus.

As far as free insurance that comes with credit cards, at least for Chase, it doesn’t cover return flight expenses at all. It covers non-refundable expenses, such as if you have a non-changeable air ticket.