First - the good news: the Heimdall rescue did the trick! the phone is alive once again, and it even reads the SIM!. YES! THANK YOU!!!
However, Odin still completely ignores it. And frankly, I think it might have been my attempt with Heimdall that messed things up to begin with.
So, do you have any ideas for ways of getting Odin to talk to my phone?
EDIT: I found a good guide for using Heimdall. Still, if you have any ideas on how to make Odin be my friend again, I'd really appreciate it.