And the Corleone look Michael gave Tom

My take, for what it is worth!

Fredo seemed pleased that he was being included and proud of his speciality, showing people a good time

I didn't read too much into Fredo's "Havana's great, it's my kinda town" as anyone visiting a 'new' city could have made that same or similar comment, impressed with what he saw from the airport to the hotel
Also Michael knew a place the brothers can spend some time together

Besides Fredo would have to quickly 'research' the local drinks, local entertainment even perhaps 'sampled' the superman club! that night since Fredo was going to show Geary and some government people a good time the next day Fredo's speciality