As far as I know, you cannot force times in the agenda view. The agenda view will always just show a list of events for the time period, and the times of each events. It does not show up all times and whether an event occurs in that time like the day or week view.
You can modify what the time looks like in the agenda view by using eventTimeTemplate, which is specifically for the time displayed in the agenda view for events.
You can go to this Dojo and create multiple events, then go to the agenda view. You will notice the agenda view simply displays all events and times they occur. It does not display any times events do not occur, so you cannot really just add time windows to the agenda view.
You could perhaps set the majorTick to 60, and go through each row tr in the k-scheduler-times and hide all the ones you don't want shown while hiding the scheduler row as well somehow.