I'm not going to lie here but if I only had what you told me to work with I'd get some non-conductive film plastic and insulate the metal so there is no electrical path to short out the fan. I can't guess why the owner took this apart and I can't find a service manual to see if there is some missing parts.
But I could fix that given the story.
Laptop fan works fine when I hold it but stops working when I place it down into the laptop. I found that when the metal fan casing touches any metal on the laptop it just stops spinning. The laptop is an msi ge70 2pe. Any ideas on how to fix this or even about what's causing this?

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