Had that happen to suit once (at another chain). They tried to dryclean again and it got worse.

First they claimed it was not their responsibility as a third party does the drycleaning. I fought saying its outrageous if they offer the service and do nothing if it doesn't work etc. Also helped I suppose having some status with them.

After much back and forth (they kept the suit) they offered compensation when I showed them a receipt for the suit - I had to call the shop I bought it from to dig up the receipt.

I signed some document with them not admitting fault, but as a gesture of goodwill they were making the reimbursement, and that it would consider the matter settled.

If it doesn't work out at first, keep fighting your corner. Its still silly to even need to fight about it.