Welcome to the QuickBooks Community, RossBrattonIV.
I can assist you with creating a credit memo in QuickBooks Online.
When you create a credit memo, you have the option to choose the Save and send or Save and close option. To successfully create the transaction, please make sure to choose Save and close.
You can click the drop-down arrow located in lower right corner of the screen to expand the options. I've attached a screenshot below for your reference about saving a credit memo without an email.
Let me know if you need more help concerning the credit memo. I'll be sure to get back to you.