In the movie, when Jonas was running away because Jonas wanted to go and pass the wall of memory. Asher saw Jonas leave as in the book, only Jonas and The giver knew about the plan. Asher was trying to stop Jonas but nothing could because he knew that Gabriel was in trouble and he knew that was the only one that could save him and also because he loved Gabriel really much. He ran out of Asher’s reach for now and he went to find Fiona so he could find Gabriel.
In the book, Jonas