Does Timatic check the validity date on passport expiry or is it just give an OK on the assumption the person is leaving the island before passport expires? I can put in my details travelling to the US from Provo with less than a month left on my passport and I get approval as well, which I've heard isn't the case travelling to the US??? Probably too late to do much now however it will be up to check-in agent AND immigration on arrival when she gets here, both possible show-stoppers.
The UK Government website (we're a UK territory) states;
Passport Validity
You must hold a valid passport to enter Turks and Caicos. Your passport should be valid for a minimum period of 6 months from the date of entry into Turks and Caicos.
Noting the keyword is 'should', so that's where there is maybe some flexibility...