Thank you for the timely reply. I was actually able to figure it out. The issue was that an iframe holding the Google Recaptcha box inside the form was laying on top of the submit button. This happened because of a definition of iframe css in the theme’s responsive.css file specifying “auto” for the height, which was overriding the iframe’s height attribute. I was able to add custom css to specify the height for the specific use in my forms so I am good.
For what it’s worth, and I’m just going by what I understand (I know I’m more hack than expert), I don’t think that generally using a height property on an iframe is considered a good practice since it will not actually affect the size of the content in the iframe, only the space that the element uses. But I’m guessing there is a reason for this particular style.