Answer: No, his action was selfish because he didn't respect the privacy of Michelle.
Explanation: First we need to understand what the word "altruistic" means.
Altruistic means a show of unselfish devotion to helping others, it involves any actions that doesn't benefits an individual but rather benefits others around that individual. Jonson shared the information with Emily in hope of getting some benefits ( Emily liking him), that is an unselfish act and doesn't go along with the meaning of the word altruistic.