Hindawi. Among others.
JPeterson described this years ago, in his Psych field. You can tell a fake/worthless paper by looking into how many times that work is then used in a subsequent paper. Remember, science is built. One discovery then leads to others. But, if the first “discovery” is crappola no one is gonna bother using it as a reference since that is tantamount to plagiarism. You will get caught when the 1st one crashes and burns.
He looked into tens of thousands of papers and none were used elsewhere. Nada. Practically no paper/thesis in recent years in his field is used anywhere else. They are just printed out and .......... abandoned.