Hacks Indic fonts on Kindle Keyboard 3

I have a kindle keyboard 3. I tried to read bengali ebooks there. Bengali is a language of the indic language group. It has complex glyphs.

The kindle keyboard cannot show the complex glyphs. It breaks them into simple ones and the result is unreadable.

I have see Kindle paperwhite can display complex glyphs properly, without any modifications.

Can anyone help me by telling me how can I use the same firmware as kindle paperwhite (atleast the rendering engine) in kindle keyboard?