Fixing spotlight "code validation failed" errors?
I suspect it is a problem with a plist entry, first obstacle is knowing what file or app to look in...

I have been trying to fix a similar issue from mdworker scanning apps that was traced to an old style InfoPlist.strings for a Classic/OS9 emulator

Just after I succeeded in fixing that (it was quotes within quotes) I started to get 


  mdworker[97078]: code validation failed in the process of getting signing information: Error Domain=NSOSStatusErrorDomain Code=-67062 "(null)" UserInfo={SecCSArchitecture=ppc}


I am not sure yet as I have just expanded the detail of logs I am looking at and not confirmed the source of the new message. It should have been there as I rolled out my fix among the many copies over a few days but was not seen until I just went deeper in logs.

Hope that helps if you are still stuck! I may report back...