The IATI documentation for the @ref attribute says:
Machine-readable identification string for the organisation. Must be in the format {Registration Agency} - (Registration Number} where {Registration Agency} is a valid code in the Registration Agency code list and {Registration Number } is a valid identifier issued by the {Registration Agency}. If this is not present then the narrative MUST contain the name of the organisation.
The Dutch government supported activities in Zimbabwe:
Not only are those ref codes malformed, but some of them also appear multiple times, representing different implementing orgs. Is it the reporting organization that’s using this identifier in an odd/wrong way, or merely a result of bad model mapping?