This is correct, though it ignores that scientific empiricism is a pragmatic empiricism. Whenever recent experience contradicts past experience, a new model has to be constructed and previous "knowledge" to be disproven. That's the falsification process. If a theory doesn't pass it, it's replaced with a new one, or changed so that it fits the new observations of reality. It's self-improving.
And since we can't always validate that what we are seeing is the correct process we need for understanding a certain phenomenon, scientific concepts have to be constantly submitted to the falsification process. It's far from perfect, but it works, and more importantly, it gives results. It's knowledge, that will stand until new notice.
This is mostly correct, but the justification process in science is created through the falsation criterion. Sure, it's bound to be changed whenever new experience challenges the scientific paradigm in a certain field, but there is a large step to be taken for you to say that it's not "knowldge", that can't be used, and it won't award results if we attempt to use it for something. This is more true for solid scientific theories, like the Theory of Evolution, with literally hundreds of thousands of peer-reviewed articles, detailing experiments and observations, backing it up.
The problem with employing axiomatic principles like 'unnecessary suffering is bad' is that, contrary to 'I occupy a point in space-time', you can calculate how much you occupy in space-time, but you can't do so for suffering. What is 'unnecessary suffering'? If there is unnecessary suffering, that means that 'necessary suffering' exists. What is necessary suffering and why is it necessary? Why is unnecessary suffering unnecessary? At which point does 'necessary suffering' turn into 'unnecessary'? How can you understand whether a individual is correct or incorrect when they make a statement like "[X] action that was taken created necessary suffering"? If there is an action that creates suffering, that action probably had motives and tried to meet certain ends. How can you justify those ends in order to state that such action created 'necessary' suffering, or the opposite if it is to be qualified as 'unnecessary'?
You can't do that like you can with axiomatic principles of Geometry and Mathematics, which they themselves are problematic. Axiomatic principles are bases in which knowledge can be build upon, but are less than reliable in plenty of cases. Geometry changes its axioms like creationism changes its "science", not because of that they are wrong, but it's problematic in and on itself.
You are right, but it is a very simple situation most people could agree on, it doesn't generate more moral relativism and subjectivity. Either you lie or you don't, and most of the time, the only thing at stake is scientific credibility. The reasons scientists wouldn't do it is because they could lose their careers.
Take animal experimentation and everyone will go nuts to either side.
Empiricism doesn't make sense as an epistemological theory? Oh boy, oh boy. And do you think Rationalism does, when it categorically fails to promote any real justification for practically anything?
Yes—and the reason this happens is because knowledge is justified. That means, we can analyze it, measure it, and create an understanding of it that adapts it to our observations of reality, something the scientific method is really good at. Hence why science, social, natural, and exact, is shit at measuring morality, because it can't be done. Thus, it's not justified, and it's not knowledge. Epistemological justification is done through empirical understanding. If empirical reasoning can't create justification for a set of objective moral principles, it means that either they are unobtainable at the present time, or they simply don't exist. Like Big Foot, dragons, God, the feathered snake, and other mythology, which are unfalsifiable, and thus either yet not possible to observe currently, or inexistent.
Protip: remember that no anthropologist worth his salt believes in a blank state anymore. It's entirely possible for subjective cultural values to be partly influenced by behavioristic patterns present in the human psyche.