When Carl visits Pop Stenvold's shop, Pop sets down his newspaper, but when the scene's picked up by another camera, Pop's newspaper is back in his hands.
While investigating the damaged telephone, Carl discovers it takes 420 psi to crush it. His research discovers that the knight's total weight is over 400 lbs. Assuming the knight put all of his weight on one foot, the total crushing pressure distributed over the surface area would be significantly less than 400 psi. The knight would have had to have stood on one tipped toe (one square inch) to crush the phone.
When the knight kills the ward captain, as the crossbow bolt is fired, it dips immediately after release, indicating that the bow's torsion is low.
Kolchak breaks into Hydecker Museum to take photos of the Knight in "action". But all he's taking is still photos of a suit of armor, which wouldn't prove anything. One shot that Kolchak takes is of the Knight facing him and standing still. All of the photos would look like the Knight is standing still and not moving.
Guy De Mettancourt lived in the 12th Century, but his ghost wears plate armor that wasn't invented till the 15th Century.
When the knight kills the ward captain, it can be seen that the crossbow is being fired by a bare hand (the prop master) and not the armored glove the knight is wearing.
It's not clear if the knight is a ghost, or a physical presence, or what. It can seemingly teleport to the locations of some of its victims, and knows who people who never been to the Hydecker are involved, like Remutka and Hockings. But then it also has to break into places, like Musso's penthouse, instead of just teleporting.
When describing the "Canadian-American Leisure Corporation," Carl first uses the abbreviation KALC, then, moments later CALC.
The weapon used to kill Brewster Hawking, and described by Carl, is properly called a military flail. A "mace" (which was Carl's term) is a wooden handled weapon topped by a knobbed or flanged metal ball. (If topped by a spiked ball, it is called a morning-star.)
Mendel Boggs denounces Minerva Musso for manhandling a fourteenth century shield, and then likewise dumps it on a table.