Is a contract with an individual representing a patient organisation still needed if the engagement involves no remuneration but provides travel/accommodation?

Yes a contract or agreement is required which must be agreed in advance,  specifies the nature of the services to be provided and the basis for remuneration where relevant and what, if any, expenses will be reimbursed.

Clause 24 provides more information on such contracted services.  

If expenses are to be reimbursed this should be stated in the agreement/contract and disclosed as required in Clause 24.6 and 29.