There is no issue with the first bullet point, that's exactly all it's supposed to do is summarise the contractual framework by listing the main and secondary options plus the version of the contract. The first bullet point only needs to list "and Option Z". The Works and Site Information are incorporated by reference further down the General section in Contract Data and Z clauses could be incorporated similarly with a statement like "The additional conditions of contract are ... in document X of the ITT".
I would conclude that the Z clauses have been incorporated correctly and even if "Z" wasn't listed in the first bullet point due to an admin error but it said "The additional conditions of contract are ..." further down I think if it came to a dispute about it they would probably still be incorporated.
I would conclude that the Z clauses have been incorporated correctly and even if "Z" wasn't listed in the first bullet point due to an admin error but it said "The additional conditions of contract are ..." further down I think if it came to a dispute about it they would probably still be incorporated.