There’s nothing to check. You’ve come up against a documented limitation with Condensing.
Please read the Condensing Calculations and Limitations page in the manual: Condensing calculations and considerations
If these players only switch instruments for entire movements, consider using an entirely separate set of players for these movements. Then assign both the Bb Trumpet 1 and C Trumpet 3 Players (two separate players) to the same part layout. Rinse and repeat for the others.