Sounds like you're doing the right things. Did you just leave it sit in a clump, or try to help attach it to some driftwood or similar? If you haven't already, you might try putting that last little clump on some driftwood with some fishing line or thread. I've been lucky with it, I even managed to have it grow in my Betta gallon bowl at work with a standard fluorescent over top. I also have some extra growing in a little 1.5 gallon tank that is sitting outside on my back porch getting about 4 hours direct sun, and the rest "bright shade". Maybe you could try resurrecting yours that way?
Best of luck, I'll send you some if you lose it all, just pay shipping.
Best of luck, I'll send you some if you lose it all, just pay shipping.