That's an inductive argument, not a slippery slope argument.
All inductive arguments are fallacies, in the rigorous sense. Only
deductive
arguments are rigorously valid.
Although they are fallacies, that does not mean that inductive
arguments
should be ignored. They simply need to be recognized as such--that
there is
necessarily an element of uncertainty about the conclusion.
Then you're using the word "fallacy" in a different way than normal humans use it. That might be a more correct way of using it, I don't know, but just be aware that people will take it differently than you mean it. Calling something a fallacy sounds like you're saying that it's incorrect and should be completely discounted.
I don't think anybody believes that their "slippery slope" argument is conclusive proof, we all know it's just one consideration in the debate.
Alex