I'm so sorry for the loss of your shrimp. But sadly, learning the hard way is part of this hobby. And your re-tellings of your experience will help newbies to the hobby like me.
As I have had the same experience with driftwood, although self-collected, I do not recommend taking the chance and putting wood into a tank. As badflash said, it tends to rot too fast and pollute the water with organics.