yes, science never proves anything, it can only be falsified, but at least it agrees with the empiric data. You have nothing to verify your theories against for the other disciplines.
Science has nothing to verify either!
The criterion of verification is the key problem of logical positivism--which is as dead as a theory can possibly be. It is dead
by its own merits--it disproves itself. Yet here you are, positing it (as almost all science advocates do!) as though it were trivially true. It isn't, and that, too, is a critical part of why scientism is such a grave concern.
You have staked out the position that science is the one and only valid path to truth. How do you aim to prove this claim? You can't use science to prove that only science can prove things true!
gravity still exists, and except in extreme cases it does not matter much whether you use Newton or Einstein
I wager that if he had been completely off we would not call them laws any more, much like we generally do not take spontaneous generation serious any more
He was completely wrong though. He said his equations described existence. They don't. They are only an acceptable approximation, and that only in a narrow slice of reality.
Most things don't actually work the way he thought they did--that's why we need to account for time dilation even with just ordinary satellites orbiting the Earth, and why we can use gravitational lensing to look
behind stars, and a bunch of other things.
His theories are,
objectively, wrong. We should have jettisoned them the moment we had the chance--that's what Popper's theory of falsification says. But we didn't. It took
mountains of evidence, objective and unequivocal repeated
proof that Newton's laws were wrong, before we finally accepted that there were alternatives.