Cubs know the personalities and which guy(s) need what. I trust Cubs to make the right call as to who should be up (and why).
Perhaps Young didn't fit the clubhouse perfectly (tho' I've never heard anything negative about him), perhaps they think Canario will really benefit watching the MLB Cubs work their processes and the wisdom of at least some of the guys who have good Spanish.
Whatever is the reality, it would really be fun for Canario to hit one to the moon in a Cub uni this season!
Both Morel and Canario have holes in their games, however, IF they ever really figure it out, watch out! Both have elite raw talent!