Also, I have ridden the monorail (express and resort line) in several times, never been asked for a room key or anything. Anyone can ride any monorail, they are not held for resort guests.
Sorry, but you are misunderstanding the point of the following replies-
1. b) If the day is an EMH morning at MK, you should arive around 7:30 at the TTC. After parking, you will be held up prior to the monorail since you are not an onsite guest…
b) -guests with WDW resort ID can board the Resort Monorail and ride to the MK front gates. (Two brief stops, Poly and Grand Floridan) before the MK gates stop.
We are talking about TTC and MK's AM EMH (Extra Magic Hours.)
On those specific mornings, guests arriving at TTC headed for MK are "held" at TTC
and the MK Express Monorail is delayed from taking TTC guests to MK until much closer to 9AM (regular park opening time.)
That's because non-WDW resort guests can't enter MK between 8AM and (approx.) 9AM
as that first early hour is exclusively available for WDW resort guests.
Since most resort guests take the resort buses directly to the MK gates area and NON-WDW resort guests, for the most part, arrive via TTC,
in order to avoid a huge back-up of guests at the MK gates,
some guests who can and some who can't get into MK before 9AM,
they hold the MK Express monorail at TTC until closer to 9AM.
WDW Resort guests (who CAN enter AM EMH)
can board the Resort Monorail (which will be operating) and ride it to the MK gates.