Neither are correct, I wrote about what happened here: https://gbatemp.net/threads/usb-y-cable-usb-hub-usb-peripherals.636729/Powered hub? hmmm..... something nefarious happened but just so you understand... in a y cable only one of the leafs has a data connection. the other one is purely for pulling power from another port. So that data connection from the wii to the hub would not be needed.. if the connection didn't work you would just need to swap the two sides of the Y adapter. USB is an end to end negotiated connection and 3 devices talking on one cable is not a supported function. (HDMI is the same, any HDMI splitter requires a chip to receive the hdmi signal and then output the signal to two female cables).
As for why your drive may have died... the 5 volts should remain 5 volts because it is hooked in series and not parallel, so either the drive was bad to begin with or the usb hub was bad and was outputting outside a safe voltage range?
The drive I used was a drive that has worked flawlessly (with a Y-Cable in both ports) for a year.
After attempting the setup pictured, it worked exactly the same, full speed, identical to my eye, for about 2 hours. Then the Wii suddenly crashed dumped.
When I looked at the drive it was perfectly wiped (even the title label was gone) and blank. However my drive still showed almost full capacity, so I thought to do a scan for errors, and when I did, the complete totality of my drive's contents were placed into Found.000 as file fragments.
After a full (not quick) format, with zero fragmentation, it works in the Wii but it's at quarter the speed it used to run at.
I only wrote USB Data for the hub in the picture to specify that it was with the Hub's data cable, not a powered one. It was never powered when this happened and although I don't have a cable the Hub does have an optional powered input that's never been used.