In Brahma-sUtras, the sannyAsis are referred to (III-4-17) as *Urdhvaretas*. This means those who don’t waste their energy in low activities of the senses, but take it Brahmasutras and also upward into noble paths.
Reading through those portions of the the Achary’a Bhashyas on them, it is clear that they (the SannyAsis) are the ones who are qualified for the third stage in advaita-sAdhanA.
A jnAni has to be a sannyAsi; should be.
Brahmasutra has another name for it: ‘Bhikshu-sutra’. Bhikshu means sannyAsi. One who lives, not on one’s home-food, but on BhikshA (formal ritualistic begging) is called a bhikshu.
The book that is totally dedicated to enquiry into Brahman being called ‘bhikshu-sUtra’ shows that it is the sannyAsi who has the right for this v idyA.