It is hard to say where the script is breaking down. I don't have pgp, so don't know what -fea +VERBOSE does... The best I can do is give you some hints on where to troubleshoot.

Is the problem that the body is not decrypting properly? or that the body is simply not part of the message when you receive it? Does the body "look" right (obviously if it is encrypted you won't be able to read it, but it should take a fairly obvious shape). How does the body of the message compare to other pgp encrypted email messages that succeed? Is the email missing anything (headers, separators) that is necessary to decrypt it?

If you print out the message to STDERR (or your error log, or even just back to the browser) does it look like an email message? Does it look like a pgp encrypted email message?

Do you know for sure that just sending the output of pgp as the body of the email is what you need?

Answering those questions should narrow it down for you, anyhow. Sorry I can't be of more help.