Here is the text of the Seruv for those interested,
I'm posting the English translation below:
The three of us sat together on 11 Tammuz 5770 (June 23rd, 2010), and we deliberated on the dispute between Mr. Israel Meir Kin and his wife, Lonna, and his repeated refusal to arrange a Get (writ of Jewish divorce) for his wife in accordance with Jewish law. Despite extraordinary attempts to appease him and to mediate between the two sides, Mr. Kin adamantly refuses to divorce his wife in accordance with Jewish law.
Therefore, we determine that he is considered a “Sarvan” recalcitrant) and does not comply with Jewish law, and the ramifications of this status are elaborated in Shulchan Aruch, Yoreh Deah siman 334. It is incumbent upon anyone who is capable, to influence him to free his wife from an agunah’s chains and comply with Jewish law.
Problems with this Seruv:
1) Meir Kin deposited a Get with a B"D
Update: Unfortunately both Rav Yitzhak Peretz, head of the Rabbinut Rabbinic courts, and Rav Shlomo Amar, chief Rabbi of Israel, say that this particular Beit Din, and the Rabbanim that run it, are not qualified to judge Gittin nor are they recognized by Rabbinute. A Get that is not universally recognized is pointless, which is what this discussion is all about.
IF the State of Israel will consider the children Mamzerim if she remarries using this Get, surely the majority of Chareidim, at least within Israel, will as well. Which puts us in no better a position that with a Get Meusah.2) There is no B"D Kavua in the US so no B"D has the right to judge a person in the US without his consent(at least according to Rav Moshe Feinstein).
However, that of course does not mean that Nidui is at all justified. .
3) Basing a seruv on Y"D 344 in a divorce case is absurd, it's the hilkhot of Nidui
4) Since they are proclaiming Nidui(I have no other reason to think that they would be invoking those halakhot) any resulting Get would be possul Get Meusah according to all opinions.
5) The B"Y Eh"E 134 says that it is impossible to kasher the Get until it is no longer in the power of the those forcing him to force him... That is highly problematic.
Above the blog owner says,
"Rav Schachter and his supporters keep insisting that Rabbeinu Tam allows all actions which are not physical and are not nidoi."
However it would appear that is not the case, Rav Schachter also does Nidui when it suits him.