Yes and yes!
The small one can be used exactly like a well flavoured summer squash. Indeed that is how I use the late developing winter squash fruits, taking them off the plants so they can carry on developing the well formed storage fruits.
Baker Creek say Queensland blue matures in 110 days so quite a late ripener.
http://www.rareseeds.com/store/vegetables/squash/winter-squash/?pg=4My Jumbo Pink Banana Squash, all thirty of them
, that are marked as 105 day maturity have been picked for a week to ten days but I like to get an early planting with protection.
Winter squash need "curing" off the plant in order to set the skin and condition the flesh. They often change colour somewhat once picked so you may find your Queensland Blue ripens in store.
Of course you may have it eaten quite quickly anyway.