Sometimes because of the strap, the latch will actually open when you pull on the release handle but the door will not because of the effort needed.
Attempt to open the cargo door by first ensuring it is unlocked then have one person hold open the handle on the outside while the other person pushes against the door from the inside. Use caution to not damage the trim with the inside force. If this does not release the door it is best if you take it to the Toyota dealer for repairs. Noting the year of make they will most likely be able to help you for free (under warranty) while still being able to get paid from Toyota for any repairs. If you attempt this repair yourself many of the fasteners for the trim are hidden by the closed door and will, most likely, cause damage to the trim in attempting to remove with the door closed. Let the dealer suffer through it and if they damage the trim they will, most likely, be able to replace it under warranty. I hope this helps. Happy Motoring!!!