add more subprops ( epo:leadBy<epo:hasMember)

[VladimirAlexiev]

For every pair of props with the same domain and range, consider if one maybve is subprop of another (I think that's one of the OOPS! checks).
(Note: this rarely applies when the range is skos:Concept because concepts are distinguished by ConceptScheme)

Eg here:

epo:hasMember  rdfs:domain  epo:OrganisationGroup ;
        rdfs:range   <http://www.w3.org/ns/org#Organization> .
epo:leadBy  rdfs:domain  epo:OrganisationGroup ;
        rdfs:range   <http://www.w3.org/ns/org#Organization> .

I think you need epo:leadBy rdfs:subPropertyOf epo:hasMember