Our body is city of 9 gates. My question is how a devotee leaves a body and is different from a Yogi who quits his body for Moksha. Generally in Tantric Yoga it is said one whose soul exits through Sushumna Nadi/skull will get Moksha. If that's the case, how a devotee would leave his body for Moksha?
Have a look at the following verse from Kathopanishad's (Kath UP) Tritiya Valli:
ShataichekA cha hridasya nAdyastAsAm murdhAnamabhinihsritaikA |
TayorddhvamAyannmritatvameti vishvanganyA utkramane bhavanti ||
Among the 101 NAdis, that emerge from the region of heart, only one has gone up to the Brahmarandhra. During the time of death, only if the [the vital breath] is made to travel upwards through this NAdi bestows immortality or Moksha. If this moving out [of the vital breath] happens through any other NAdis then SamsAra Gati (i.e rebirths) is the result.
Kath Up 2.3.16
There can be many NAdis but the three principle ones among them are - IdA, PingalA and SushumnA. Of which the SushumnA is the one that is only capable of bestowing salvation.
The one NAdi being talked about in the above verse is the same SushumnA which ends in the orifice at the crown of the head (Brahmarandhra).
The Kundalini Sakti is of the form of eight Prakritis (matter) and coils itself eight ways or (times). The movement of Vayus (vital airs) checks duly the food and drink all round by the side of Skandha. It closes by its head (the opening of) the Brahmarandhra and during the time of (the practice of) Yoga is awakened by the fire (in the Apana); then it shines with great brilliancy in the Akasa of the heart in the shape of wisdom. Depending upon Kundalini which is situated in the centre, there are fourteen principal Nadis (viz.,) Ida, Pingala, Susumna, Sarasvati, Varuni, Pusha, Hastijihva, Yasasvini, Visvodhari, Kuhuh, Sankhini, Payasvini, Alambusa and Gandhari. Of them, Susumna is said to be the sustainer of the universe and the path of salvation. Situated at the back of the anus, it is attached to the spinal column and extends to the Brahmarandhra
(From the minor Upanishad called Sandilya Upanishad)
So, the summary is, it does not matter who's getting Moksha - it can be a Yogi, one who is not a Yogi, a devotee or a non-devotee - but the method remains the same for all of them. That is the vital breath must leave the body only through the Brahmarandhra in all such cases.
So, to answer your question, even for a devotee, the vital breath must leave the body through the Brahmarandhra only, if he/she has to get Moksha.
If it moves out through any other orifices then rebirth is the result.