I was reading this thread and I have some to add
My husband is also Cuban and I am all too familiar with Cuban politics and laws. I was VERY surprised to hear that your 30 year old husband only found out about Cuban law regarding living/staying with a Cuban family after they threatened him with jailtime. The laws surrounding Cubans and foreigners are very widespread and commonly known in Cuba. From when my husband and first I met and during my several trips to the island he made it very clear that we could only stay in a Casa Particular (rental houses that have been authorized by the Cuban government to rent to foreigners) and that we needed to be very careful with the authorities because of this. Cuban law prohibits Cubans from mingling/covorting/ speaking to a tourist (unless your job requires it i.e. for those working in a hotel).
I think there are 2 main reasons neither of your lawyers nor employees at the Consular Offices mentioned these laws when you got married:
1) they most probably well assumed that at lest your husband knew the legalities (as I said it is widespread throughout the island and everyone I know there is aware), and
2) because a marriage between a Cuban and a "foreigner" is not illegal. The marriage process is perfectly legal and Cuban authorities cannot prohibit this.
I think you were robbed of $3,000.00 as the paperwork for the marriage process does not require this much money.
All this being said, the Canadian embassy in Havana does tend to scrutinize applications for couples that do have an significant age difference. I don't want to come off as negative nor discourage you but I know several cases (where the wife is sponsoring their Cuban husband) where the PR was refused. Just make sure youhave more than enough proof to show them your relationship is genuine and you should be okay.
Cuba is a beautiful island with even more beautiful people but there is also alot of political unrest, economic problems, food scarcity and is generally very poor. Many there call it a prison floating in the middle of the Carribean.Yes, there are several proud Cubans that have no intend on ever leaving their country but there are many more that are aching to get out. This is a reality and the CIC in Havana knows this. As robertbola mentioned age difference is a concern when sponsoring someone from a poor island like Cuba. I know of a lady that is several years older than her Cuban husband and he made it clear he was excited to be coming here because he was tired of running out of hot water for days on end. It wasn't because he wanted to be with her, he was simply fed up. It's Cuba's reality... thousands of people frustrated at their confinement and lack of resources.
Gather more than necessary and ensure you have a strong file. Good luck!