Where can one find the dd-wrt you used for your c7? I have the same device and have been unable to get it to flash anything other than official firmware.
Here is the exact `factory-to-ddwrt` image I used (this will depend on which version you have): ftp://ftp.dd-wrt.com/betas/2019/10-15-2019-r41328/tplink_archer-c7-v2/
