That won’t solve anything if your card templates / database is messed up.
What I find odd is that your code for the front cannot be right at all (why would it work on ankiweb, that doesn’t make sense to me).
Take this picture:
You have a div which contains a span. But that span is empty. There should be a field there. You should press the Add field button and insert the correct field for the front. If you do that, you’ll notice that your problem goes away.