Freepbx and dinstar sip trunk registration

hello experts, We have a freash installed freepbx on aws with public IP and one dinstar with private IP but internet connection. so you need to do simple: register dinstar as sip trunk on freepbx with username and password based. keep in mind dinstar is not having public IP and and if you are not expert in this sip trunking, dont waste your and mine time. network diagram: aws---(amazon)-------FreePBX-----------------(INTERNET)-------------------ISP------------home user----------internet-------- Dinstar on local IP you need to connect dinstar with freepbx so that incoming and outgoing calls can be flow on freepbx form dinstar. I can provide you remote access with 30 min time if you will be not able to configure in 30 min, no payment will be for that work. keep in mind payment will be only if my task completed in time line and both side comminication will be happen properlly.