This function returns account filter by id.
jetapi backup -F getAccountFilter -D '_id=5b28f9f4d5ac5e5ed5049f82'
https://hostname.example.com:2087/cpsess##########/cgi/addons/jetbackup/api.cgi?function=getAccountFilter&_id=5b28f9f4d5ac5e5ed5049f82