As far as I have heard from sources both from within and outside of habad the story is as follows:
The late rebbi of the habad hasidim was at the time waging a ferocious campaign for the change of Israeli Law .
Advocating for the insertion of the words giyur kahalacha in the text.
Pertaining to the type of conversion recognized by the israeli government , ensuring israeli gov rejection of Reform conversions made in the US.
The rebbi of habad decided to put a certain politician who was a member of the then government , into herem.
As a result of this p’s inaction in following the habad rebbi’s directives to either fix the law or resign.
One of the roshei yeshiva of torah vadaat , besides being an immense talmid haham , was an old hasid , still a mekurav from the rashab’s times.
He was appointed as RY by r shrage faivel Mendlowits in tora vada’at.
He was the author of ashkavte devei rebbi – a historical and scholarly sefer recounting the illness and the histalkut of the rashab and the beginning of the rayats’s leadership of the habad , who had a very privileged position in the rashabs household at the time and therefore a unique view of what was going on.
This RY also authored other sfarim , printing his hidushim on shas.
The rebbi of habad insisted that this talmid haham should join him in pronouncing the herem on this politician .
Apparently the rosh yeshiva did not think that the herem was justifiable al pi torah , so he did not join in this herem.
Whereafter the habad rebbi made some public remarks against the rosh yeshiva, whereafter the redifot against this rosh yashiva started ,
Those redifot had as a direct result that the RY died in his home.
After the RY’s petira, the rebbi of habad publicly disavowed any responsibility for the RY’s demise .
Ad Kan the story.
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We should not use this story to throw mud.
We should however learn from this about the possibility within habad of someone implying that the leader of habad could be mistaken .
This RY implied it and ended up paying with his life.
The RY obviously held the rebbi from habad in high esteem .
Otherwise he would not be his hasid and attend all those public events with his rebbi.
Nevertheless , as a talmid haham who was higi’a lehora’a , in his opinion at least , said politician was not deserving to be put in herem .
He was not disrespectful.
He just held that his rebbi happened to be mistaken in this one instance , which is perfectly acceptable according to Jewish halacha and tradition.
So he abstained from the herem.
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