Charliehall,
The name calling of the Rabbi Tendler you refer to is because in the eyes of most Rabbonim in the Torah World Rabbi Tendler is to qoute many “a second rate scientist and thrid rate rabbi”.
And yes over and over his psakim have been held up and shown to have no basis.
A Doctor who is off the beaten track and passes out medicine that is of dubious origin and is proven to be dangerous in many cases is called a quack even if he has a “degree”.
The Rabbi you refer to is essentially a quack.