Consider this new and unfortunate situation

You no longer have access to your most important computer.
(and your most destroyed robot)

Actually, losing just the computer is not the end of the world.
Of course it will cost money if you want to replace it but you still have other computers at home.
Often, more important than the computer itself is the data it contains. But this is not the biggest problem either. You have a redundant copy of everything important.
Except maybe the recent change to the robot's software. But with the robot destroyed it's not so relevant any more.

No, the biggest problem is that you lost the only CT card you had.
Finding a replacement is going to be a gigantic challenge.

How could you think that it would be a good idea
to take such an important item with you for this silly walk
and leave it unguarded?

It was your window to the the world.
And now the window is closed.
And you can't just reopen it.
You look where you expect to see the window but you see a windowless wall instead.
A wall which never had any windows at all.