Try to do some search engine searches on your victim, or perhaps even look through Leaked Sources, I'm sure you can find something about them, such as IP addresses or so. If anything, even if you're looking to DDoS them, and you already have their IP address(es), it's most likely that you would require to pay a few dollars to send an attack, considering a majority of these services aren't free..
You can try to recover your account by contacting Wolfteam's support, I'm sure they can help you if you have certain documents with you such as proof of any payments (Considering your account's worth hundreds of euros, right?), or so. If possible, ask them to list all of the IP addresses that were logged when logging onto your account, that may help you obtain the victim's IP address, say that you will need it for security reasons.