There is an EEM Hostname setting in Service Desk Options Manager, is that installed or enabled or however that shows as on? That field, when installed, is used as a key to encrypt the PAM Password, if you fill in the password field then install and set the eem hostname the password wont be encrypted correctly.
Try to reenter your PAM Password, save and restart Service Desk.
If that does not work I would recommend that you open a support case with the Service Desk group to investigate and resolve this for you.