Well if you school won’t let you download unreal through the launcher, you could user the source build.
In an emergency case I still use a 2.5mm hdd or ssd then use an usb to sata connector, that would be a tad better than a regular flash drive(as i do this for my project backups) then just put the unreal version on there.
Other wise you’ll have to convince (i guess your IT or Department) to update the unreal version.