Responsible disclosure is to prevent harm. You think about your disclosure options and pick the one that is best overall weighing the impact and harm.
They're already infected - or so you claim.
I get that companies want to use responsible disclosure as a mechanism so it can save face and their reputation, and if both are possible at the same time then sure.
But if you think you're right, you have to pick one and live with the consequences; and its not that hard to pick the right choice.
In fact, if you don't make the right choice you need stop misusing the word “responsible disclosure”.
Publish the URLs that prove they're infected. Auto update it whenever one get's fixed.