I've come across an issue that is displaying empty form fields on a product when editing in Catalog. In Commerce Manager however, eveything looks and works fine.
The product page is showing the product like expected.
I think you should check if you selected the right version in Catalog UI. Commerce Manager and the product page should be using the published versions.
Are you using ServiceAPI with the DisableVersionSync flag set to true?
We've only found this issue on one product, not all of them. On other products it works as expected.