aliasing spot colors together and output in Acrobat Pro DC

Hello,

I need some help... I am unsuccessful at being able to alias spot colors to a single spot color and then output the aliased solution in Acrobat Pro DC.

Print, Separations / Ink manager / alias spot color 1 and spot color 2 to spot color 3. 

Print preview looks appropriate, but when spot color 3 is printed, the merged images from spot color 1 and spot color 2 do not show up.  Only the original image of spot color 3 prints.

When I perform the same function in InDesign with the same PDF… all three aliased colors successfully united image named spot color 3 as they should and I can output getting the desired result.

What am I missing when I perform this function in Acrobat Pro DC?

Thanks in advance