The only way to band-aid it is to modify the Sketchup::Model
class, which is a no-no for extensions. (It will be rejected for publication on the Extension Warehouse.)
But if you want to do it only for yourself, then:
class Sketchup::Model
unless method_defined?(:deleted?)
def deleted?()
self.valid?() ? false : true
end
end
end
There is no way of forcing the DC code to use a class refinement, because that must be done from the DC ruby file that needs to use it.
What can I say? I have reported it publicly and privately multiple times.