Why can I edit PDF Form Data with Preview but not with Acrobat DC?
Without seeing the PDF, it's impossible to give an assessment. However:

The irony of PDFs is that the format was designed to enable standardized documents; but the flexibility of the format means that PDFs can be created in lots of different ways. Sometimes the syntax can be incorrect, or the various elements unsuited to their intended task. 

While bugs do exist in Acrobat, Adobe are the creators and custodians of the PDF format, so in the absence of other information, I would assume the PDF document is at fault. 

It's also possible that 'rinsing' the PDF through Preview may cause problems, as MacOS's Quartz framework can only write a subset of the PDF language. 

In Acrobat, you should be able to Preflight the PDF (Command Shift X) and check that its syntax is correct and that it's suitable for the job required: you can also Fix any problems found. 

Acrobat should also let you create new form fields, or at least, write text in the correct position. If you can't do those things, then something is very wrong indeed. Try creating new forms or text in another PDF document.