@Sarah2230 I email a map and photos to my guests all the time using the coded email address and it doesn't bounce back, so I'm not sure why it's not working for you. Are you sure you are entering the entire coded email address correctly?
What I have found is that the email attachments aren't always visible to guests, especially if they are accessing their email via their phone rather than desktop. I always ask the guests to confirm whether they received it or not, so I know. In that case, I ask them if they would mind sharing their personal email address and give them mine at the same time. None of my guests have minded this at all and readily send it to me. They always get the attchments if sent to their own email address.