Originally Posted by
Venezuela-Miami
Interesting. Have you tried with a good ol' brick and mortar travel agency? may they can construct the itin.
If you haven't added the last sentence confirming your own experience, I was going to challenge it by intuition because in flights from Venezuela to the US (restricted as a single itinerary) they definitely check thru, so they surely can but probably is an exception for the very particular situation of Venezuela.
It has happened to me twice in the last couple of years. Once was a Lifemiles copa award ticket connecting to a paid copa ticket, the 2nd time were two paid copa tickets.