The mere fact that your description
pretty much confirms that the rollers are shot (which does change the
effective spacing when under load) is enough to verify that there's a
lot of wear, and sooner or later this will result in a failure.

so, you are saying that roller wear has a limit

a. what is the limit then?

b. other experts said, the only thing that matters is chain pitch, and
roller wear doesn;t affect that

wle.