Ok, so what should I do?

[PJinIA]

I got my 08 Tahoe LTZ on August 1st and right away took it to Best Buy to get an I-Simple thing installed so I could control my Ipod with the radio controls. Soooo, here's my question...I haven't driven it for 4 or 5 weeks because I didn't want to mess up my chrome wheels. Anyway, I went to start it Thursday and it was totally dead so my husband jumped it that night and let it run awhile. Next day I went to start it and it fired right up BUT when I backed out of the garage I noticed the camera screen was dark...I hit the power button, nothing. All the way to town I tried to get the power to come on but it never did. My son works at the Chevy dealership where I bought so I drove there thinking it was just a fuse or something simple. That wasn't it so he took it over to the service shop and drove it in and had the service manager come over and he said they'd take a look at it. Well a couple hours later he said they might replace the battery because it shouldn't have gone dead sitting in the garage for a month and then he said the whole radio/nav/camera unit was fried. He said they checked the wiring schematic and it wasn't the same as their book showed. This was Friday night and he wanted to keep it till Monday because they can't get parts till then. I didn't think of the I-Simple thing until I was on the way home. So any ideas...could the Isimple thing have drained the battery and then fried my nav system when it was jumpstarted? I thought the Ipod thing was just a plug & play thing....would Best Buy have changed my wiring during installation. I'm freaking out now thinking my dealer is going to tell me this device is going to void my warranty and I'll to replace the radio/nav/camera out-of-pocket. Should I call them Monday morning and tell them I had this installed or is that going to be obvious to them anyway. Sorry this is such a long post but I was hoping someone else had one of these things installed and knows if this can cause problems with the nav system? Thanks for any help you can give me.