I am trying to convert the Number 2 from a text to "stroke to path," and while inkscape did it, the number is no longer a solid object.  I am trying to Union the #2 to the hexagon, and it's not working.  

I think you need "Object to Path" rather than "Stroke to Path"

I attempted to "Object to Path" afterwards, after selecting the #, inkscape says its not a path.  

That's a strange thing to say,

Does the bottom bar say "group of X objects"?

This is after I "object to path," but inkscape will not allow me to "union" the two items together.  

It says 2 objects selected of types Group, Path in layer 1

I found a solution.  Thanks for your help, much appreciated @doctormo

Used this: convert a text line into object, apply Path > Object to Path (or Shift+Ctrl+c ), 2> then appy 'Path>Dynamic offset' (or Ctrl+J ). The text line (let's say "test") can be converted to path