We looked into your mail and found that it is corrupted:
1. Mail is Unicode .msg file, it states that all text fields are Unicode encoded, but the Body is stored using the Windows-1252 encoding
2. After decoding Body using Windows-1252 I saw this:
<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml"
As you can see, this is Html Body, not a Text Body.
The problem seems to be within the generator of this .MSG file.
Please note that you sent the MSG attached to your email. In this case we are not sure whether it was not modified by other mail servers when being sent. If you want to be sure, that we have exactly same .msg as you are working with, please send us the .msg file ZIP compressed one more time. And we will check it once again. Thank you.