31 - TRAVEL COSTS OF PEOPLE OTHER THAN STAFF

A collaborator of one PP is seconded from an institute outside the project consortium. This external institute pays the collaborator salary. The collaborator actively participates in the activities of the project. The PP reimburses the costs incurred by this collaborator for his duty travels.
Is it possible for the PP to claim for reimbursement of this collaborator’s travel costs made on behalf of the project, even if there are no hours worked by the collaborator paid by the PP?
The PP has the mission module, with all the various authorizations and support documents presented by the employee plus, I think, the reimbursement through an ad hoc coupon (the payment mandate is obviously cumulative and not specific). The PP has the duty travel authorization, the documents supporting the expenses as well the reimbursement made by the PP on behalf of the collaborator. If yes, are these “Travel and accommodation costs” or “External expertise and services costs”?
What should be the documents supporting the expenses incurred?

No, Travel and accommodation costs refer to the expenditure on travel and accommodation of the staff of the beneficiary organisation for missions necessary for the project implementation.
If compliant with the rules of “external expertise”, the costs are eligible under that BL.