Yep, I've seen that the article that you linked is updated on 9 June 2020 and the link changed...
I download the old firmware file: 'http://linuxtv.org/downloads/firmware/dvb-usb-dib0700-1.20.fw'
Will correct that ASAP, but give me some time, will keep you updated, think tomorrow I can update the files
EDIT: So the tuner is working with the LibreELEC drivers?