Googlebot looking for lowercase version of verification file

Looking at the error log for two sites with sitemaps, I see a file does
not exist error for a lowercase version of the verification file.

http://www.projectmessrocks.com
http://www.sladesfoodandspirits.com

When I successfully verified the sitemaps the name was

GOOGLEe570b73969f9b58e.html

However, the error log reports googlebot looking for

googlee570b73969f9b58e.html

I have now created a version of the verification file with the name in
all lowercase to see if I have any better luck having one of these
sites indexed.