In answer to your question, yes, you can access any of the children of RobustList within the onSetupItem by using this.$.
if it's a List. Check the documentation here: https://github.com/enyojs/enyo/wiki/Lists . Because of its flyweight pattern there's only one active set of controls within the List so you can refer to them directly by name.
You wouldn't want to use this.$.
to access the items in a Repeater because there are many copies of the components (one for each row). Use the passed in reference (e.g. var item = inEvent.item;
) to access the items within the row template.
I also notice you use 'fit: true' on a couple components in the list. You can only have one fit: true component in a FittableColumn/FittableRow. Neither of those is actually in a fittable so it won't probably do what you want.