Are the International Kosher certifiers rubber stamping the Heimish certifications?

Yes they are! sadly, to the kosher consumers detriment.

"Broineh-zeklach" pesach hashgochas.

Pesach "grubbeh-zaltz" Salt packaged "without a mashgiach" in a facility that packages chometz  items all year. Pesach Potato starch from a foreign facility without a mashgiach. Pesach Sugar packaged in a facility that previously had flour in their silos. Pesach Oil processed with citric acid, (in a facility that uses chometz, kitinious citric acid) without a mashgiach for the production.