I have never seen DJ strictly enforcing hand baggage rules... I would say you have 97% chance to be allowed to take it with you.
I guess since the OP has said no more that it all worked out OK.
My experience is that on one occasion (years ago now) DJ did enforce the rules on me in ADL. I also heard that yesterday in Brisbane (now) VA did so to a passenger connecting to an international flight.
I am interested since I am connecting VA-AR in March. Sadly the bookings are on separate PNRs. I would like to take an international size carryon, but really do not want the hassle I heard yesterdays poor BNE-SYD pax went through.
(The story I heard was the unhappy pax retreated to DFO near the airport to buy a domestic size carryon, leaving her international size bag at the shop for pick up on her return. This was done (hearsay) because VA insisted on checking her carryon into the hold, and refused to budge. With plenty of time (which I would not expect to have) the pax found an alternative solution, but was very cross about it all.)