Conflict with NextGen, buttons show – only partially

I have installed SU on a site that uses NextGen. I added a button to a page and it only allows the button itself to get a certain size. I deactived NextGen and that was the culprit, but I have too many things using it to remove NextGen. I tried both checking and unchecking Custom Formatting. Neither worked. I tried checking/unchecking skip default values as well.

There’s a conflict (it’s a relatively old Theme, so that may be the culprit). But if you’ve seen this issue where the buttons only get a certain size, maybe someone hopefully has a solution. Really love SU and want to use it on this site.

Thanks for any help.

https://www.icedamremovalguys.com/save-on-your-next-ice-dam-guys-service/

Notice the first button. Text is large, but that’s as big as the button will get.

https://www.ads-software.com/plugins/shortcodes-ultimate/