There is more. Once you have those files the IDE needs to have access to the internet to download the 64board packages. Without that the IDE can't compile your sketches.
I suggest that you contact the IT department.
Alternatively, find another Windows computer with the same architecture (32bit / 64bit), install the IDE there, download all needed board packages an next copy the installed board packages over to your PC.
Same approach for libraries or you can download them (from e.g. github) and manually install them.