I gave up on this and then bing bang boom I found the hidden secret to resizing any single cell with word table using 2016.

Here's the big secret in case it hasn't been posted yet.

Are you ready?

TRIPLE CLICK the cell to highlight the entire cell and its contents

That's it. Now resizing works without affecting any other cells.

Did I win anything? Or has this been posted already? lol also I found this post via google so at least others will have the answer now.