I ended up hacking a way around this by modifying the Build.PL file to add a 'includes_dir' hash member with a known string to replace and then at compile time run the Build.PL file through a perl regex, replacing the known string with a real-time location of the perl headers.
Ugly.
I actually ran into this exact same issue with quite a few of the newer Build.PL packages. Seems like there is a hole to fill for these packages that do not build with the 'standard' build methods and for perls that are installed in non-standard locations - separate from the source.