Benidorm council only wants empty properties to house Ukranian refugees because of safeguarding of minors.
If you have an empty holiday home you would like to let Ukrainian refugees for a period you could go to the Social Services Bienestar of your Ayunamiento and see if you can register. They do not want shared accommodation ,spare bedroom etc.
In Benidorm you can go to:
Concejeal de Bienestar, Carrer Pintor Lozano, 03501,Benidorm