Ambedkar was a great hindu then Buddhist they do not eat cow , there is no need of purifying , it is needed if cow eating cutwas or any christian enter a mandir then we need to purify the mandir .hopefully it worked. any purification is a good thing.
Ambedkar was a ok guy, quite smart and well trained by his gurus. so if it was just him, there'd have been no need for such purification. But as it happens a lot in the India and its satellite nations in the Indian subcontinent, many impure and lower people adore and join great ones like Ambedkar and the mob if it entered holy temples, it is a good idea to purify.