Hi,
the info I have received from the people in the know is that :
it's definitely not normal to receive such messages, i.e a user seemingly prevented to access an MSI that has just been extracted from a setup.exe to a temporary folder he should have full access to, which is what is happening here. I don't think the max path length is being hit here either, there is nothing peculiar about it that would make me inclined to think that's why the file "can't be found".
I would say the correct way to attempt to resolve the matter is to try Microsoft specialist tool and see if that helps:
https://support.microsoft.com/en-gb/mats/program_install_and_uninstall
Please report back when you have tried it,
John