So they will be fined €2,500 and the game, which was a scoreless draw, will be awarded as a 3-0 win for Monaghan.
Harps, who now lose a point from the game, can now appeal by arbitration.
The club had played Aaron O’Hagan in the game three weeks ago when he should have been suspended for bookings picked up in the A Championship.
Meanwhile defender JP Gallagher has left the club due to work commitments.