The problem was solved and I was able to succesfully withdraw some LTC. In the end, it just seems Exmo is not able to cope with the current high demand.

Same problem. Please confirm my email! Request #279044

I get the same error when withdrawing ("error 10325: need to confirm the email"). Chat support told me to send an email to support@exmo.com which includes your EXMO username & email address and a request for account activation.