I agree that there is nothing wrong with using multiple bits for the same horse. I have several myself that ride in different bits. One example, my semi-retired reining mare at home, on the trail or with a lesson student rides in a 3 pc. snaffle, showing speed events she goes in a hack, in the reining pen she rides in a shanked bit w/a port. It's not to cover up holes in training, it's different bits for different uses.
I (and most will) completely agree with you buck on the point of not bitting up to cover up holes in training. I don't believe that to be the case with the OP. Her horse is shown in multiple disciplines, more than one bit makes sense.
Life is like a camera. Focus on what's important, Capture the good times, Develop from the negatives and if things don't work out, Take another shot.