Owners leaking washing machine – who pays

Question.

An owner in our plan contacted the OC to advise water was
dripping through his ceiling. Inspection showed a large amount of water pooled in the ceiling and had formed a bubble in the paint finish. 

The OC’s plumber called the following day and found that in the unit above the rubber inlet supply pipes running from the laundry tap to the washing machine had perished and leaked water which had flowed into the unit below.

The OC’s plumber replaced the inlet supply hoses and his bill was paid by the OC and an account sent to the owner, whose washing machine
had leaked, for re imbursement to the OC. 

The issue that arises however is that the repair of the ceiling below is under our excess ($400) so is not claimable on our building insurance. 

Who in this instance is responsible for payment of the repairs to the ceiling and also the repainting of the same ceiling given that is was the owner's washing machine that had caused the damage?