The view from inside the helmet does not match the shape of the visor.
When questioned why Halsey's arm is missing, Locke says Jul 'Mdama was responsible, when it was actually Commander Palmer who shot it off. While Commander Palmer shot Halsey in the arm during the events of Halo 4's Spartan Ops, the arm was amputated due to the Sangheili's limited understanding of Human anatomy/medical care, while still a captive of Jul 'Mdama between the events of Spartan Ops and Halo 5:Guardians.
After one of the times defeating the Warden Eternal, Locke and his team encounters the Master Chief and his team, who look like they have just walked in the door, despite the door being shut for the entire time needed to defeat the Warden Eternal.
On Sanghelios, Locke says 'Clear the area from enemies', which is a grammar mistake.