Hello! I am helping a client with building some pages and these pages include a triggered send (via REST API) that fires off an email from an account with Tokenized Sending enables. I looked in a lot of places and I can see a lot of information about the fact you will need to have the token and email saved in client Database, but how would this work with triggered sends that you just enter your email address and that email address might not even exist in client's database?