Epic doesn't use confirmation email after account is created. You literally can make account with any email address without owner of that email knowing that you used that address.
Wait really? That is the stupidest thing I've ever heard!
Yeah this is true, a few weeks ago my epic account was hacked, I e-mailed epic and they asked me to provide:-
• Your public IP address(es) (IPv4), which you can find by searching "What is my IPv4 address" in your internet browser; if you use multiple devices, please include all IPv4 addresses
• Date when you created your Epic Games account (which you can find in the inbox of the email address you used to create your account)
• An invoice ID for any Epic Games purchase you made on the account (the Invoice ID begins with an "A," followed by 8 digits; example: A12345678)
• Locations (city, state/province) where you made purchases on the account
• Original display name for the account
• Last 4 digits of the first payment card used on the account
• Date of your last login
• Names of any PlayStation, Switch, Twitch, or Xbox accounts connected to your Epic Games account and the dates when they were connected
I was able to provide all the information except credit card info (as I had never bought anything) and the date my account was created years ago as I tend to delete unimportant e-mails. They e-mailed me back saying that they wouldn't help me. So I tried to make a new account using my other e-mail to find, like you that some one else had used it to create a account. I never received any e-mails no confirmation e-mail or spam etc.
The weird thing is when I e-mailed them to delete that account they never asked for any proof that I owned the account, they just deleted it straight away.