I wanted to add a comment to this discussion, but could not, presumably due to age. However, I can confirm that I encountered an issue with a transaction that was declined due to:
The given name on the account and/or the account type does not match the actual account.
I haven't confirmed that this is solely due to the given name, so it's possible that the account type is wrong. I do know that the name on the account is 27 characters long, and we had to truncate to 22 chars due to the requirements of the API, so it seem likely that it is the account name that is the actual issue.
If there is some way to get around this limitation, or to verify which part (account name, account type) is invalid, please let me know.