What happened to the german robot "joker"? (Spoilers!!)

They tried to use a german special police robot on the "Masha"-roof. But not even that one could stand the 12000 Roentgen radiation and died after a few seconds. Since it was no
longer manouverable, it must have still been on the roof when the "bio-robots" had to clean up Masha. And yet, in all of the 120 seconds of the cleaning scene, the robot is nowhere to be seen. What happened to it?
I know from the original footage, that they used remote controlled cleaning machines and the radiation did indeed render them useless. Some of them even fell off their roof. These robots then had to remain where they were for a certain period of time. Due to their heavy contamination, they also must have been thrown in the reactor or lifted with a helicopter and disposed somewhere else. I wonder how they did that.

Btw: the poor guy that we follow on the masha roof, whose foot got stuck under a chunk of graphite and who stumbled and fell, spend full 120 seconds in the intense radiation -
life expectency cut in half.