Sorry for delyed response here, but I'm wondering if you ever found a solution to this? If not, could you link me to a page where you're having this issue? This may be some kind of compatibility issue with jQuery and IE11, but I'll be happy to run some testing on it. For what it's worth, I did find a threads about a similar-sounding issue on Stack Overflow: https://stackoverflow.com/questions/25077612/jquery-not-working-with-ie-11. But also, you shouldn't need jQuery to embed a HubSpot form on a non-HubSpot-hosted page.