Is anything incumbent upon me if I throw the pebble at the beginning of the throwing by those around me and in their same direction, due to the severe crowding and my inability to see the location of the Jamarah?

Striking the target is a prerequisite for a valid stoning of the jamarat (definition). If there is doubt about hitting the target, then that stoning is insufficient. This is the view of the majority of jurists from the Hanbali, Maliki, Hanafi, and Shafi'i schools.

If the number of pebbles doubted to have fallen into the target is three or more, the pilgrim must offer a fidyah (definition) for abandoning an obligatory act, which is sacrificing a sheep. If unable, then fasting ten days: three during Hajj and seven upon returning to one's family.