Of course it is. The experiment is whether a sample from a healthy animal, lacking the suspected pathogen will give the same result as the sample from the infected animal when cultured.

Then explain to me why it doesn't involve actually putting samples from healthy animals through the same exact process it says should be done to samples from sick animals?

If It did involve that, Koch would have discovered asymptomatic carriers decades before Typhoid Mary.

Here we go again - Koch didn't work with viruses, but with bacteria he could observe.

Here we go again, confirming that this entire topic is not relevant to your claim that viruses aren't real.

Since Koch was fake and gay also, let's put him and his postulates aside. How does one go about proving a hypothesized pathogen caused the symptoms or the disease observed to fulfil the scientific requirement for knowledge?

First off, I'll say the fact that it's called "Koch's postulates" and not "Koch's experiment" ought to be a very big clue to you that this isn't what you think it is.

19th century scientists did not choose their labels arbitrarily, and "postulate" means something very specific that totally undermines your attempt to use it as any kind of proof for anything.

Postulate means ASSUMPTION! And things are not proven with assumptions.

That being said here is the answer to your question....

You first start by devising an experiment that proves contagiousness, which is absolutely trivial and easy to do. You just start by recording the fact that the disease can be transmitted from person to person.

Then you continue demonstrating contagiousness over and over again, as you record the disease moving farther and farther away from patient zero.

Along with proper controls this will demonstrate that whatever causes the disease is self replicating, based on the simple fact that dilution would effect the concentrations of any poison or contaminate as it moves more and more steps away from patient zero.

However, if you can demonstrate that patient 1,000 is just as contagious as patient-zero, then you are at the same time establishing that whatever causes the disease replicates inside the body and isn't subject to being diluted as it's transmitted from person to person.

Okay, so now you've established that there is something self replicating and contagious that makes you sick.

Now you can devise other experiments that involve testing and culturing samples from the sick people to see if you can find any differences between their samples and that of a healthy person.

Before you know it you're discovering viruses and performing experiments to determine in what environments they can live and replicate.

This is how science works. You don't start off with 4 statements and base everything around merely assuming they are true.

You don't get to step #50 where you discover the virus can't live on it's own, and then assume that invalidates all the other 49 steps.

You start with the absolute most simple and basic things you can prove for a fact, which are NOT POSTULATES.... and you continue building new ideas that you can prove on top of that foundation.

Which by the way, is exactly how germ theory of disease was developed.