This is really just an addendum to the last post. While looking for something else I noticed the following:
In David Jackson’s A Saint in Seattle (Wisdom Publications, 2003) there is a section based on the biography of Ga Lama Jamyang Gyaltsen (alias Jamgyal, 1870–1940) by Dezhung Rinpoche.* There it says that Jamgyal first heard the name of his root teacher, Khenpo Shenga, some time after being thrown out of Tharlam Monastery (for trying to reform the discipline there). The expulsion happened when he was in his late twenties, i.e., the late 1890s. Some time after this he met an old monk from Gemang hermitage in Dzachukha. Jamgyal asked him who was in charge there now that Orgyen Tendzin Norbu had passed away (In Tibetan: deng sang bla ma o rgyan bstan ‘dzin nor bu gshegs zin pas gdan sar su yod). Following Jackson’s chronology, this conversation must have taken place in or before 1900/1901. The monk informed Jamgyal that a scholar named Gyalkhang Shenga had taken over, but that he was no different from his teacher: “The golden sun may have set, but the conch-like moon has risen” (gser gyi nyi ma nub kyang dung gi zla ba shar). As soon as Jamgyal heard Shenga’s name, he felt intense devotion and pledged to study with him.
Jamgyal studied with Shenga for a full five years at Gemang before he began his major project to publish the works of the great Sakya scholar Gorampa Sonam Senge (1429–1489). Jackson estimates that Jamgyal worked on the project from 1906 to 1910.
All of this further supports the date of around 1900 for the death of Orgyen Tendzin Norbu (and makes the 1910 date suggested in Enlightened Vagabond even more problematic). But, of course, nothing here is definitive.
Jamgyal, incidentally, went on to become the third khenpo of Dzongsar Shedra — after Shenga and Öntö Khyenrab Chökyi Özer — and, through his efforts in publishing the writings of Gorampa Sonam Senge, helped to transform Sakya scholasticism. What became of the old monk is not recorded.
*Kun dga’ bstan pa’i nyi ma. rJe btsun bla ma dam pa ‘jam dbyangs rgyal mtshan gyi rnam thar mdor bsdus skal bzang rna rgyan. New Delhi, 1983.