The Spire Motorsports driver will be replaced in the No. 7 Chevrolet Camaro by Josh Berry in Sunday’s race.
LaJoie is 29th in the championship standings after a 16th-place finish at the Indianapolis Road Course. He was going to start 24th at MIS.
Berry will be pulling double duty as he replaces Michael Annett in Saturday’s NASCAR Xfinity Series race. Annett continues to recover from a leg injury has caused him to miss several races and dropped him outside of the playoffs.
Berry made his Cup debut earlier this year at Dover, finishing 30th with Spire Motorsports.