Nonpayment of of business dues with fraud methods

Hello Sir, We are propritory bussinessman. We have client pvt ltd partnership company for whom we are regular supplier of samples or prototype for checking purpose This time we have supplied the material after formal business quotation to client and formal email confirmation of the order from them.But there are no purchase order or email confirmation on the pricing for 4-5 orders which we have delivered in a span of 1-2 months Sept -oct 2019 .After supply of material of 3+ months client is saying we have charged them more and he is declining to pay the full invoice amount 7-8% and asking us to accept the debit note of amount on two of the invoices what he feel appropriate.When we replied to formal email of with attachment of debit note alongwith with his company ledger and declined to accept the debit it through email requesting him to pay to rest balance of other invoices where over charging issues are not there but then he upped the ante and replied back saying that our samples have quality issues asking us take it back and will not pay any of the amount and his client rejected the samples but fact of the matter sampling exercise is successfull and his client has moved up the process of production order which our client is going to do mass manufacturing for .presently production moulds are in making phase only .In our quotation we had clearly mentioned that quality issues to be notified within 2-3 days after receipt .We have the phonecall records and in person discussion audio records where he mentions overcharging only and not an quality issues anywhere .So in this case can we file criminal case with police since we are not interested to file civil suit in view of time line to get judgment although it will be on our side only.we think in view police deparment involvement he may accept to settle it without any debit note.we don't have any document proof of delivery challan etc but his men's material carrying cctv videos can be provided. Again here would like to.mention that this owner has lot of political connection locally and notorious records of civil suits and non payment of dues to his suppliers like this.please suggest.