So, clearly the original Buddhists in Tibet included a monastic Sangha.
The monastery was so important that the king was advised to bring the
supreme Ngakpa, Guru Rinpoche to Tibet to ensure the success of the Samye
project.
This first transmission of Buddhism was just that-- the complete Buddhism that
existed in India-- both Monastic and yogic. Thus from that time forward there were
always two sanghas. Nyingmapas generally do not speak of a distinction between
Monastic and lay, rather we have two sanghas --and there are also householders who
are practitioners bu who were not members of the white sangha of yogis. One doesn't
have to be ordained in either sanghas to accomplish high realization, nor is ordination
a criterion for being authorized as a lama.
Nyingmapas generally feel that the view of the Sarma is overstated when they say
that Atisha had to come to re-establish Buddhism that had become corrupted during
the suppression. The monastics were an easy target, but the ngakpas were not so easy
to take out and could pass for bonpos!

We like to recall that Lord Atisha once met
and debated with the Omniscient Mahapandita Rangzom Chokyi Zangpo and lost!
Lord Atisha's response was that had he known there were such great Buddhist scholars
in Tibet, he would not have come.
Well the "new-fangled" Buddhism came, and a new schools were born sakya, kagyu, etc.,
and this also resulted in a new school called "old school." It had its original monasteries
and continued to build new ones such as Kathog ca 1160, Dorje Drak in the 1300's, Mindrolling
during the time of the Great Fifth Dalai Lama... All these followed more or less their own
local traditions. Some were sacked by invading foreigners, sometimes by followers of other
traditions.
In response to the sectarian warfare, a new model was proposed: the Rime Movement.
Some Scholars now say that because of the Terma tradition and the textual basis such as
the Rinchen Ter Dzod, that the Nyingma is now the most recent and modern of the Tibetan
Orders. That may be overstated.
As the role of non-monastics, I think we only need to look at who has been selected to lead
the community in exile. Dudjom and Khyentse Rinpoches, and Mindrolling Trichen were Ngakpa.
Penor, Trulshik and now Taklung Tsetrul Rinpoche were/are monks. So it is easy to conjecture
that equal status is given to the two sanghas in the minds and hearts of Nyingmapas.