I don't think he anything to lose either, not with the current status of the death penalty in Colorado.
Not too long ago, with this case in mind, I looked at what was going on in other states that have the death penalty. Nebraska really jumped out. It's next door to Colorado to the east. They had the death penalty, but there hadn't been an execution since 1979, so like Colorado, it wasn't carried out for many years.
In 2015, the Nebraska state legislature actually replaced the death penalty with LWOP. A petition gathered enough signatures to put it on the ballot for for 2016, and an overwhelming majority of voters determined the fate of the death penalty. They wanted it.
In August of this year, I believe on the same day CW was giving his porch interviews, a man who had been on death row for 39 years in Nebraska was executed by lethal injection.
When CW and his defense team were discussing the plea, I imagine the probability of the death penalty actually being carried out was something they also discussed. He would have been informed about the current status, in Colorado, I'm sure, but I wonder if they also brought up what just happened in Nebraska to point out there were no guarantees?