You can reference a dynamic member list inside of the api.Members.GetMembersUsingFilter. See the example below using the member filter you referenced. You can put any member filter that works in a Cube View in the memberFilter argument of that function.
Dim sDim As String = args.MemberListArgs.NameValuePairs("Dim")
Dim oEntDimPK As DimPk = api.Dimensions.GetDim(sDim).DimPk
Dim oEntMemberInfos As List(Of MemberInfo) = api.Members.GetMembersUsingFilter(oEntDimPK, I#ICEntities.CustomMemberList(BRName= BRName, MemberListName= MemberListName, Param1 = Param1, Param2 = Param2, Param3 = Param3), Nothing)