I wanted to reach out in response to your well written essay illustrating the influence of Persian on the Bengali language. As a literary scholar, I am always fascinated by the pre-colonial cultural exchanges in South Asia, and I hope you are pursuing a much larger project dealing with early modern South Asia.
I would think the language of the Mangalkavyas are also Persian-ised or may have been influenced by Musalmani Bangla. To my knowledge, I have not seen any major scholarship dealing with the Persian influence on Bengal. Scholars do agree though that the influence has been massive.
Michigan State University