SwingsitlikeHogan
Major Champion
All historical films have an element of guesswork in the conversations, liberties taken with timelines and certain settings. They need to happen to keep the story moving, to make things fit within the time allowed. If you kept rigidly to the story then you would need a mini series, not a film. You need to suspend the pedantry for a while, sit back and enjoy the ride.
If you find an interest in Bruce and fancy learning more in the context of a ripping yarn - I recommend the Nigel Tranter Bruce Trilogy. He really brings the main players of late 13thC and early 14thC Scotland alive.