Or... you're just wrong. Which is the case here. As has been pointed out several times.
You can't show that it's true that "it's possible to know all things that exist", as has been pointed out several times. You even know why, because it's been explained over and over.
Tell you what, if you can show that "it's possible to know all things that exist" is true, I'll send you $500. Seriously.
All you have to do is provide evidence that it's impossible for there to be an unknowable thing.
Have you ever heard of the term "projection". Because that's what you're doing.
You know, throughout this and every other thread you participate in, you're constantly being called out by non-theists (and as I recall theists as well) as having fallacious logic. Do you honestly think we're all incorrect and you're correct?
So do it. Show that your assertion "it's possible to know all things that exist" is true. Prove us all wrong.