Special Heading Inconsistent on site/ Theme versions

Hi.

I inherited this website from another developer and have run into a couple of issues I’ve not seen before.

I am changing the pages to include a Special Heading block set to <h2> and with custom color. On most pages, the font is consistent. But on my Contact Us page, it is a different font, even though the Special Heading block settings are identical, and the Page Attributes (Parent, Template, etc.) and Layout (Sidebar Settings, Footer Settings, etc.) are identical.

The heading I want can be seen at https://kyconcrete.org/certifications/ (“Certifications”), and the heading that is inconsistent is on the Contact page
at https://kyconcrete.org/contact/.

Any ideas on how to fix this?

Second issue: the original developer did not use a child theme. When I look at the installed themes, I see two instances of Enfold (screenshot: https://www.screencast.com/t/IQYmVDSmG). The one that is active is Version: 4.0.2. But there is another theme installed that is Version: 3.8.4. I suppose it’s okay to delete the inactive one, but want to be sure. And since I’ve never seen this before, I find it curious. Any suggestions?

Third issue: I am concerned that the developer did not use a child theme. Is there any way to install a child theme retroactively? If so, is there any way to protect any customizations he made so I don’t blow up the site?

I am sorry to ask so many questions, and I always appreciate your assistance. Thank you.