Maybe it's just dirt on the DVD lense? Unlikely as IIRC multiple lasers share the same lense but might be worth to try to clean it. Just search for some cheap CD, DVD or BlueRay cleaning disc and enter it. Wii U will tell it can't read it but...
Did you watch the part of the video that says "where to start?"
... Run modmii on a windows pc
Start the main Modmii wizard and tell it your wii is a virgin even if it's isn't, follow the prompts
Or drag and drop your syscheck.csv onto...
Here's my possible recommendations of emulators and games you could grab:
For SNES: Snes9x TX for better compatibility, and Snes9x RX for better speed.
Games: Yoshi's Island, Star Fox 1 and 2, Super Mario World, Mario RPG, Final Fantasy III...
Your IOS249 should be base 56, curre tly u have the same cios installed to slot 249/250
Probably won't resolve your issue, but still work fixing
Drag and drop your syscheck.csv onto modmii.exe and it will tell you what to do
your syscheck report looks correct.
Where are your games placed (SD, USB)? , format FAT32?
RECOMMEND ==>use wii backup manager to manage your games on your device.
Are your loaders up to date?
or see here ==>...
Did you even read the first post or the reply you quoted??
The op is using a usb flash drive and the reply is the answer. In short... Yes you can but then... This!