You need to contact them as soon as possible.
Fill out this form:
https://secure.cic.gc.ca/enquiries-...2.2041657693.1501882831-1855558094.1501882831
Then send an email to Havana-im-enquiry@international.gc.ca
If he has family in Havana, maybe someone could go to the embassy.
You need to let them know about this situation so that they can reschedule the interview.
Hi Thank you! I emailed them and I get a return message that it couldn't be sent... I will for sure fill out that form, as well as try calling again on Monday. I couldn't reach them today, didn't know they closed at 12 on Fridays, and they sent the email at 11;17 am :/ He has a good buddy there we will ask. Thank you SO much!!!!!!