The station/unit hierachy can only approve, recommend and encourage your application to DHE. If the local DHE morale suppression officer says no, then it's a no I'm afraid. As mentioned, DHE manage (and I use the term in it's loosest possible context) the properties and if their interpretation of the Rules is that you aren't allowed to have a house, or they claim there simply aren't any spares (and tweak the stats to reflect this), then you won't get one.
A lot depends on how matey your Staish is with the disgruntled semi-retired ex-RSM/SWO who holds all the keys to your local patch. Some regard the surplus scheme as keeping their empty houses in good order for them AND generating some income, others just see it as more hassle.
I wouldn't bother moving it to a surplus MQ if the decision had been forced upon DHE. If you do, they'll let you move in begrudgingly then when you come to move out they'll go over the house with a very large magnifying glass and bill you for the last five decades of wear, tear and damage. And you can kiss goodbye to any repairs during your tenancy. Allowing you to move in is one thing, but then once you're in they've got all the time in the world to remind you that you beat them.
My advice would be take the plunge (yes it hurts) and buy your own place. MQs will be a thing of the past soon anyway.