Hi,
unfortunately, things are not that simple.
We cannot scrape Whois en masse, since RIRs tend to have very strict ratelimits
on their servers. Their raw data is all we have (except for RIPE, where things look
a little bit better), which cover direct RIR allocations only.
So, if a company acquires a /22 and splits it up into four /24 networks, we will
not be able to determine the country codes of that sub-allocations, since they
simply do not show up in the data we have.
Depending on the network your superior happens to get connectivity from, it might
be a good idea to allow EU as well, since some networks are used across Europe.
Either way, using a VPN service should be sufficient in order to keep dial-up procedures
from your superior safe.
Thanks, and best regards,
Peter Müller