Maybe there's a mismatch of incident attributes mapping in \SiteScope\conf\ems\peregrine\incidentAttributesMapping.config and what your SM is expecting in the ticketing webservice. You should check your settings by comparing keys in IncidentManagement.wsdl (SM) as stated in first lines of incidentAttributesMapping.config:
# HP ServiceCenter WDSL mapping file. use this file in order to map fields of IncidentManagement.wsdl file to
# the ticket.config file.
# use this convention: <ticket.config field>=<wsdl field>.
# some of the fields are mandatory.
# some of the fields are set directly from the ticket.config file
Kenneth Gonzalez HP Support
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