Although he is described as a three time Medal of Honor winner when Walker is shown in full dress uniform his decorations lack the five starred ribbon indicating the awarding of the MoH never mind one with two oak leaf clusters indicating two subsequent awards.
While in Zemo's safe house, John Walker states that the Dora Milaje won't be taking Zemo because they "don't have jurisdiction here." The safe house is in Latvia, where Walker also lacks jurisdiction.
At 16'30: Karli and her acolyte leave the cemetery without putting the stones back in place, thus nullifying an opportunity to hide another valuable there and raising attention towards the acolyte's family whose tomb it is.
At 44'38: John shakes Lamar's head but every soldier and emergency response provider know that one should not move an injured person's head when suspecting a cervical spine (neck) injury.
Lamar asks Sam and Bucky if they, "really think two Avengers can walk around Latvia without drawing attention." Sam is the only Avenger present. Bucky was never a member of the team.