Answer

I cannot confirm one standard, universally accepted Jain sadhu or sadhvi name for “the fourth devlok.” In Jain cosmology, the fourth heaven is the Māhendra heaven, and rebirth there depends on karma; monks and nuns are part of the Jain mendicant order, but sainthood by itself does not automatically decide the next birth. ( jainqq.org)

Explanation

If you mean a specific Jain story or scripture, the answer can depend on that text. Jain literature contains many birth-and-rebirth narratives of renunciants and pious souls reaching different heavenly realms. ( jainqq.org)

Spiritual Understanding

In Jain Dharma, the goal of a sadhu or sadhvi is moksha, not heaven. A heavenly birth is still within saṃsāra, while liberation is the final aim. ( jainpedia.org)

Takeaway

So the safest Jain answer is: there is no single fixed sadhu/sadhvi name commonly accepted for “the fourth devlok”; the exact name depends on the specific Jain text or tradition being referred to. ( jainqq.org)