At present, and for the forseeable future, your value as an ADI only ATCO is between NIL and -10.
There are plenty of ADI only ATCOs out there, most of whom have previous validations, who are seeking employment and advancement elsewhere at someone elses expense and getting precisely nowhere.
The only way you will stand the remotest chance of making yourself a marketable commodity is by paying for your own ADI and APS course, it would be even better if you did the APP course as well.
There are many, (mostly ex mil) ATCOs doing exactly this but using their resetlement funds to fund it and have the previus experience to get them through, some then get employers to refund part of the course costs.
No airfield is going to fund your courses or offer you employment, you have to make the commitment to funding and passing then you might just get somewhere.
You've clearly got a chip on your shoulder about your NATS exit - hard luck and get on with life.
Think seriously about what you really want to do, whether you have the commitment and dedication to see it through, how you are going to fund it, then grow up.
Welcome to the real world.