I need suggestions for what to call this feeling: when you are unable to perform a task or get a device or function to work properly, and you ask someone for help. But as they attempt to perform the task/operate the device, you kind of hope that they fail at least once so that you don’t look so incapable.
Validation
I don’t have a particular word for that.
But I’d be inclined to say: not so easy, is it?
A good description. Maybe I’ll call it “Validationangst.”
Co-validating failure. (two words) I can make that one German word if you like.
I’d call it insecurity. 
Agree.
The feeling is “I’m feeling a little inadequate. I hope my savior doesn’t demonstrate to both of us that I’m a lot inadequate.”
Truth is you’re not actually inadequate. You’ve just found some thing that you’re not a guru at. Or the darn thing really is broken / misbehaving somehow that’s far from obvious how to remedy.
But if your goto reaction to any obstacle is “I’m inadequate”, then “false inadequacy” or “insecurity” are the words I’d use to describe that.
Face-saving schadenfreude? Since it’s already based on a German word you could add on to it - Gesichtswahrungs-Schadenfreude. or perhaps Mitstolperfreude 
Failidation.
I like that even more.
It’s hubris, or some similar word describing excess confidence in oneself. Not so much confidence that you don’t ask for help, but enough that it wounds your pride that another might be more competent.
Is there a word for when something seems to be broken, and you finally ask for help, so when you go to show them the broken thing, it magically fixes itself?
I need a word for that.
Claimbroken, where you claim the article is broken but your claim is broken instead.
I call that “lucky”
Human
Strategic incompetence.
Ingratitude.
Heh. Recently, the PTB at work have decided to task me with performing daily maintenance on a sorter on which I have had no training (or even an opportunity to observe a coworker performing it). After ONE session of rudimentary training, I have now been tasked with going solo on the maintenance action about ten times, and VIRTUALLY EVERY TIME, I still have to ask someone with more experience to assist me when a problem crops up.
I promise I’m getting better at it, though. Although not more confident. Point is, I never feel inadequate when calling for assistance. If they want a CIOSS guru outta this guy, they can send me to Oklahoma City for a couple of weeks and have me trained.
(They really shoulda tapped me for PMG when DeJoy announced his retirement. As the adage goes, Those who can’t do, teach. Those who can’t teach, administrate.)
“Dancing frog”
Gremlins.
Maybe a bit old fashioned now. I think it was used by the UK radar boffins in WWII days…