Nitya-baddha-jīva's Nitya-svarūpa is Not Intrinsically Preestablished

We know from Rūpa Gosvāmī's 'anarpita-carīṁ' verse that Kṛṣṇa descended as Caitanya Mahāprabhu to bestow that which He had never bestowed before, which is Rādhā-Kṛṣṇa-prema in mañjarī-svarūpa, by His causeless mercy. Since mercy is the act of voluntarily bestowing a thing upon one who does not have it and does not deserve it, a jīva must therefore receive his nitya-svarūpa from an external source, Kṛṣṇa, who bestows it upon him by His will upon being pleased. Hence, a jīva's nitya-svarūpa is not preexisting in him.
If we accept that a baddha-jīva's nitya-svarūpa is preestablished in him since eternity, then he must inevitably realise his nitya-svarūpa or siddha-deha upon attaining perfection via any process for realising Kṛṣṇa authorised by vaidika-śāstra and prescribed for the yuga he is living in. Thus, there would be nothing to bestow due to his nitya-svarūpa already preexisting in him, and moreover, mercy itself would have no role in bestowing a siddha-deha in a…