I don't want to sound like a total dick, but I took a look at the pics you took pre-install viewtopic.php?f=27&t=22643
Personally, I was expecting most of the framework to be shaven or trimmed in some way.
But, you have to think about why the cubby ends where it ends and why there is an overlap between the F500BT and the cubby frame.
Parts are made to fit a certain space, hence why some modders are asking what size screen would best fit the cubby space.
Also it was a cubby supplied by yourself and with that you asked them to fit the F500BT with your supplied cubby, and in doing so basically allowed them to try and fit by any means neccesary.
They tried, failed and then fitted the F500BT the best way they saw fit without using your supplied cubby.
Yes, you should have checked the cubbys condition before you left the premises, but I am guessing you didn't.
Whatever happens with the cubby afterwards, whether you chuck it in the bin or try to sell it to recoup funds does not fall into the fitters responsibility once you left the shop.
I'm not trying to take the mick, just saying what I think about what I see.
I don't know hoe butchered the retractable cubby is, but if it was me, I'd have alook and see how the F500BT is currently fitted, then possibly cut the retainig section off and match the cut on the retractable cubbly, then plastic weld the two pars together and file smooth the joins.
Like I said, I'm not trying to take the mick, merely trying to help make the best out of a bad situation.