Hi,
To be sure, I just verify my last backup by Titanium, with these parameters Backup All Apps and their Data, and find no kbd file. Sorry for you :-/
But it is quite normal : you have to specify what Titanium have to save FROM YOUR point of view, not from Android or a particular App point of view ... Titanium can't be aware of what path you specify for KeePass kbd database !
And IMHO, the Titanium documentation could be perfectible : Backup All Apps and their Data is equivalent to Backup All Apps and their Parameters.
Regards