Can't comment on iCloud (because I am a proud BlackBerry owner!) but OneDrive works fine for folder syncing purposes, although trying to access the OneDrive website from your browser is blocked.

If it's important to maintain connectivity, I'd recommend setting up a VPN anyway. You might be able to get a free trial that lasts long enough for the trip, or if he's going to be there for a longer period then it's probably worth the investment. PM me if you'd like a referral code for Express, which will give both of us 30 days free.