Does the incident of Shankara meeting a Chandala prove that Shankara never had realization?

Question

According to Advaita Vedanta, things like caste, gotra, etc, will cease to exist after realization. But when Adi Shankara met a Chandala in Varanasi, he asked the Chandala to move away from his path. Chandala inquired that whether Adi Shankara is asking my body to move away or the real me to move away. Then Shankara responded by writing Manisha Panchakam. Later it is believed that he accepted the Chandala as his disciple.

Now if caste or varna cease to exist after realization and Adi Shankara realised himself, why did he practice untouchability?

Answer 1

There is no single authentic biography of Sri Adi Sankaracharya so far as I know. I am quoting Sri Ramakrishna:

Shankaracharya was a 'brahmajnani' but initially he did have the 'vedabuddhi'.He did not have the [required] conviction. A Chandala was coming carrying meat, while he just completed bathing in the ganges. He told the chandala: "Oh!you touched me!" The Chandala replied ":My Lord! Neither did I touch you nor did you touch me.The Pure Atman is beyond body and the twentyfour principles. Then Sankara became illumined.

(Reference:Kathamrita, Udbodhan, page 217, 15 June 1883).

Many Acharyas maintain the Varnasrama Dharma after being illumined for maintaining the social order by the way.

Answer 2

No one can get Jnan without the grace of Shiva.

वन्दे बोधमयं नित्यं गुरुं शङ्कररूपिणं। यमाश्रितो हि वक्रोऽपि चन्द्रः सर्वत्र वन्द्यते।।

That Chandal is believed to be Shri Vishveshvara Shiva himself. It might be that Shankar got enlightenment after that incident occurred as this incident is said to be happened when Shankaracharya was of 16 years.