You were 100% right. Once I added the form name, everything worked fine.
Here's something you should be aware of though. I used bootstrap elements to create the original form, and it only creates a form ID. For whatever reason, it does NOT create the form name. When you create a form in Dreamweaver, it created BOTH the form name and the ID.
Should the form creation options in bootstrap elements be updated so they do it like Dreamweaver? I think a lot of people will run into problems because forms are missing the name, and both your time and theirs will be wasted on troubleshooting this. I think most people would assume your extensions, being designed for Dreamweaver as they are, would create form tags just like Dreamweaver does so you don't run into issues like this.