epc3208 or epc3928

Hi all, i need help. I have much valid macs but modem no go online becouse he not find valid certs. I have two friend with legal modem with epc3208 and epc3928 . How can i read and download certs from modems and put in my epc2100 or sb5101e with haxorware. Provider is the same. I am always use macs from docsis 3.0 modems and worked fine 46mbps is max download speed but now cmts change base stations and not working anymore. Can someone put tutorial or link how to read and download then put valid certs. What i need of equipment to do this. Sorry of my english thanks all