Well I would agree but than it is not specific which part has Generic support. It could be the video grabber part which seems also on your device correctly be found. To be honest I still believe there is just a problem with the driver loading with the right parameter as you still get the list shown in dmesg.
But as written I have my doubts that loading the driver correctly make this work with DVB-C. You always can try to make it runing on a windows PC to validate.
Yeah, I would try my luck returning that shit based on false advertising and get a prober DVB-C device.
Anhyhow if you wait 4 months you can get hundreds of those DVB sticks for free as all the people using them for DVB-T can not use them anymore and will just need to throw them in the bin
But all of this also depends of what you get on your DVB-C
Seriously? A DVB-T2 compatible stick for 3 Euro? Maybe you should delete the ebay URL in your browser and tear out the “e” and “y” keys from your keyboard