Copy Datasafe backup DVD to USB Drive

I was trying to restore my n5110 to factory condition using the Datasafe recovery DVD as I have done many times before but this time after it restored the first DVD and asked for the second, my DVD drive decided to stop working. So I was stuck with half restored system that won't boot up (so I again installed windows 10 by booting from a thumb drive). Later I inserted my DVDs in another computer and made iso of that using poweriso and then made a bootable usb drive from that. And upon booting, it takes me to windows recovery (the list that asks to startup repair,image restore etc) instead of going to Datasafe recovery as booting from DVD would do. But at the end of the list there is Datasafe recovery option but upon clicking that it does not give option to restore factory image. I think it looks for recovery partition in the computer which does not exist instead of the image within the usb drive. How could I manage to restore from my Datasafe backup through pendrive? I think once the computer detect it is booted from usb drive rather than DVD it does not restore from the backup even though the files are exactly same in both.