the information on this case i got from Dr. Sangat Singh's book "The Sikhs in History."
on page 130-131 there is a english translation of the mata i will type it out below.
Ik Onkar Sati Gur Prasadi
Sri Akal Sahaye,
Akal Sahay,
Takht Sri Akal Bunga Sahib Ji,
Sri Darbar Sahib
We the undersigned Singh Sahibs, poojaris, Takht Sri Akal Takht, Bungaji Sahib and Sri
Darbar and Baba Atal Rai Sihibji, and Jhanda Bunga Sahibji and Shaheed Bunga Sahibji,
have examined the case of Gurmukh Singh, Secretary, and have found that this person at some
places, contrary to the Guru's devotion, has shown disrepect to Sri Guru Granth Sahib and Guru-Ansh
(descendents of Gurus) and Gurbani, orally and in print, and this leads to the conclusion that
his faith is totally averse to the Sikh beliefs and for such reasons we all Poojaris, Granthis and
Lambardaars of the aforementioned Gurdwaras, put in our hand that the said Gurmukh Singh
is expelled from the Panth Khalsa. That said Gurdwaras shall not accept his Ardaasa and shall
have no link with him.
Let all Sikh sangats be warned to avoid his assocation and following. Whosoever shall
adhere to his following shall be deemed to be a be-mukh and be taken to be liable to tankhah
(fine) and shall be punishable with the similar treatment.
This issues on 7th Chet, Samat 418 Guru Nanak - Christian Era March 18, 1887.
Signatures: Present Singh Sahibs, Auhdedaars, Granthis and Pujari. 29 Panth dignitaries
including Bhia Narain SIngh, Granthi, Gurdwara Tarn Taran.
this is the mata or resolution
on the bottom of Dr. Sangat Singh's book it says
This mata was revoked only in September, 1995 at the World Sikh Conference held under the auspices of Akal Takht and the services of Prof. Gurmukh Singh appreciated.-----