Brewology

Hello everyone.

About a month and a half ago, I installed the HBC on my brother's Wii.
He got Wii Fit on the 24th (two days ago).
Today, he called me and reported the following problems with his Wii:

1) Wii Fit said the save file was corrupt
2) The Wii would not always boot up, and he had to restart
3) When he tried to start Mario Kart Wii, it froze, then he restarted the Wii and it worked

He claims this is because of the HBC, and he wants me to pay in $80something because that's how much Nintendo will charge for repairs. (By the way, Nintendo said these things only happen when unauthorized software is installed on the Wii).

So here are my questions:
1) Did the HBC break the Wii
2) Is it smart to send the Wii to Nintendo (he already deleted the channel(yes I know logs and stuff are still there)).
3) Do you have any repair places to recommend to send the Wii so Nintendo doesn't get pissed off
4) Is there any way to back up the data on the Wii before sending it to Nintendo/another place?

Thanks

Edit: New Info:
“When i try to make a new wii fit save, it says the wii save data is corrupted and i cant make a new save. If i go to check the wii save files in the menu, I can't access them” - My brother

1) I have never heard of a problem like this before. It's possible the HBC did this, but since I haven't heard of this before, unlikely.
2) Nintendo already said they would charge you. That's the worst thing that will come from this. You could have a modchip installed, doesn't matter.
3) Nintendo won't get 'pissed' and is sounds like you have a software problem, so no one can repair it (for a reasonable price anyway...)
4) The only way to backup your data would be to go into the save files and channels area and moving everything to SD.

You mentioned your brother can't access the save files. What exactly happens when he tries?

He says:

I would have your brother post his trouble at the HBC support area here: http://wiibrew.org/wiki/Homebrew_Channel/Bugs

This sounds like a serious issue, so please keep us updated on the situation!