i mean it's a fact that those in the east had it 7 hours earlier.
whether or not anyone cheated, personally i think it shouldnt be risked at all. it's like allowing students to bring their phones to a test, proceed to not invigilate, and trust that no one did anything fishy. no reason for them to not sync up the time. imo would have also much rather them had the questions on paper just like any other test, they already printed the answer booklet afterall, and u save all the trouble with the system issues.
at the end it's not like oxford would do anything ngl. thats life, some get lucky, others not.