It would seem that Level3 has a chance to be a hero by licensing these patents to whomever for a nominal fee.
Edit: replying to the comments. Licensing for a nominal fee isnt pure, but it is practical. It would certainly discourage the trolls. I dont think you can put something in the public domain if you are only a partial owner.
They could be a hero by placing them in the public domain. Licensing them for even a nominal fee would be extortion. $1 for something that should be $0 is an infinity too large, besides it would still require you to get that license.
If someone were to charge me 'right of way' tomorrow to leave my house and the cost would only be $1 I wouldn't pay up, I'd shove them out of the way. There is not 'right' price for extortion.
That wouldn't be being a hero. Being a hero in this instance would be dropping the whole thing and asking the patent office to kindly revoke the patents as you have just realised that they are rubbish and that you are destroying your own industry for short term gain.
Licencing them for a nominal fee is still reserving the right to change your mind. Is a bit like saying that you aren't going to use the nukes, but you want to keep them around just in case you feel like obliterating anyone in the future.