Is there a search engine or site that allows people to browse multiple online dating companies, at 1 time? Or is there a site where I can research her email or name? I need to find out if my daughter has joined any more sites.

If she is underage -you can (should?) block the sites with parental control

If she is of age I don’t really think you should interfere - it is her life and I’m sorry if that sounds a bit rude it is not meant to.