Zip 19 out of MALTA?

I sent out my letters to the pdl companies using the letters offered here on the forum. Zip 19 is telling me I agreed to abide by the laws of Malta when signing the documents. Here is their wording:
The Republic of Malta is the place of the making of this
Agreement. This Agreement will be made in Malta by you signing and sending this form to us and
our acceptance and signing of this form and this Agreement shall be governed by and construed and
interpreted in accordance with Maltese law except that the International Arbitration Rules of the
ICDR shall apply to the Agreement to Arbitrate Disputes.The Malta courts shall have exclusive
jurisdiction to hear challenges to the Agreement to Arbitrate Disputes contained herein, and to all
disputes or claims arising under this Agreement that such Court, or the Arbitrator, deem to be
incapable of arbitration.

They want me to pay them $500 after I have already paid them $1,000 more than the original loan!!! Help!