Home buttom not connecting to logic board

you may be able to solder it back on. I would try it with a low heat soldering iron and some flux core solder. Bottom line when working on iPods handle them slowly and carefully. There are lot's of small and fragile parts on and in them. If there is nothing to solder the contact to on the top of the board I have had luck with using a tiny drill bit to make a small hole in the PC then solder a pc. of small ga. wire through and solder/attach the contact to it and clip it flush.