Bill, I’m not 100% certain it’s the same, but I had a similar problem where my folks send an email template (complete with SFDC merge fields) and I needed to populate a template for them based on that.

https://community.skuid.com/t/email-template-text-macro-questions

I basically just build a template in JS and then populate the text box when you click the button. I can then use Skuid merge syntax, but I lost the ability to use Salesforce template editing.

Hopefully that helps.