Assume yes, you have to show. I've yet to check-in without having to, though one trip I forgot which one I used and left that one home, but had the number memorized and rattled it off and that satisfied the check-in agent.

Call ticketing and see if you can visit a nearby ticketing office and sign an indemnity form.

EVA's credit card policy is at the following link:

https://www.evaair.com/en-us/plan-an...e-reservation/