Why does my Buy Button move to the bottom of the page on SiteStacker?

I’m trying out the buy button, and having some issues. We use SiteStacker, so my access to some code is limited, but I’ve been able to get the Buy Button onto the site (yay!). Unfortunately, it jumps out of the div I put it in, and ends up on the bottom of the page. Any explanation or ideas on why that might happen would be helpful! Then I can try to figure out how to hack/fix it…

Test page with the issue: https://www.tms-global.org/test-pages/test-page

I figured it out. Sitestacker was being weird with the div tag and broke the id reference. When I tried to fix it, I did it wrong. I repasted the original div tag, but swapped out the ’ for " and it seems to be working.