1) Danish commanding general had outguessed the German intentions knowing full well that they were going for Aalborg Airfield... an infantry battalion was placed some thirty kilometers to the north of it and on the ewe of invasion one AA-battery, the most experienced one was ordered to be ready for redeployment all limbered up and ready for moving only to be told to go back into position. Even on 8. April these two units could have been ordered to Aalborg to guard the Airfield.
Well, the problem is that the government issued orders for a ceasefire and for all units to contact the germans to arrange surrender at 06:00 (specifically citing the risk of a Warsaw style bombing of Copenhagen), and the first faldschirmsjägers dropped at Ålborg 06:15 and the transports a little later.
Now it took a couple of hours for the order to reach all units, but that was mostly infantry units in Southern Jutland already engaged and generally out of contact, local command at Ålborg would have received the order by radio well before the germans arrived.
Another thought is what might have happened had the danisk government allowed preparations to be made for a proper defense, such as preparation for demolitions of bridges, establishing bunkers and trenches in defensible locations on lines of approach etc or followed up on the various proposals to build up a rapid mobilisation force or enlarge the army etc
Now none of that will stop a determined, well supported german attack, or even hold the current attack for long, however Weserübung was always a sideshow because the Kriegsmarine wanted bases in Norway and to secure swedish iron ore.
If it was clear to the germans that it would take several days to secure Denmark and the airfield at Ålborg and/or much larger forces would be needed the whole operation might be scrubbed...