Work was done on the spoiler actuators immediately before departure. A Google translation of an excerpt from from the report shared by DaveReidUK:
Another video from the airport security camera captured images of checkpoints flight of the plane and the spoilers moving before leaving the main ramp where it was parked after passengers were boarded. During this time, it was seen that the spoilers on both wings extended, but only the spoilers on the left wing returned to a storage position, except in two cases, where the spoilers on the left wing were extended and put away twice, during the taxi to the right from the location plane parking.
During the taxi for takeoff, video from another security camera captured another image of the plane, this time from the rear of the plane, which also indicated that the three spoilers on the right wing were extended, and the spoilers on the left wing were saved.
Security video also showed that when the plane took off, and it did so with an attitude lower right wing with spoilers still extended.
Later an image of the plane captured by a witness attending a baseball game, while flying through the Quisqueya stadium. The picture showed that the spoilers on the wing right wing were still extended, but the ones on the left wing were not.