It would be very helpful if you changed the invitation to an Outing “Maybe” designation from a question mark to some other symbol. As it is now, all invitees initially have a question mark by their name. If they click on YES, that changes to a Green check mark, if NO, a Red X appears by their name. But if they check Maybe, the same question mark stays by their name. Because there in no change from the initial question mark, I have no idea if that person has considered going but is unable to commit at that time or they haven’t even gone into Scoutbook Calendar.
Perhaps you might consider changing the invitee symbol for Maybe from the (unchanging) question mark to an Asterisk. That would let us know the parent has seen/considered the outing but is unable to commit to it at that time.