When I use the List in Reminders or Reminder action, I only ever see the output show up in the designated “default list” from ios settings for Reminders. i.e. “List in Reminders” never creates a new list and “Reminder” d simply appends to the default list (it never created a “drafts” list).
For the List in Reminders, you can either change the default by editing the action step, or by placing a # List in the first line of the draft, followed by the list items.
For the Reminder action, you can change the default by editing the action.
As a ProTip™: if you want to specify a list for just a single item, just use List in Reminders with the first line being the list, and the second being the item.