I think it's still worth trying with the glasses. In the middle of the day when the sun is at its hottest. Spontaneous fires have been known to be started. Somebody's crystal ball caught fire and it was sitting inside the house.
I am mystified by the fire thing. I thought on previous Survivors they had to start the fires themselves. Wasn't Lillian proud of doing something like that? I remember in S4? people starting fires by rubbing sticks together. I don't remember them having been given matches in every previous Survivor.
I don't understand why it has become a big deal now and nobody can do it this time.
I don't recall them being given torches from tribal council to start fires either... maybe I am wrong about this.