Tamil + Malayalam I would think
@SOUTHie
My great grandma (who raised my Dad and eldest Aunt) could only speak Malayalam well as native tongue....the Tamil was just mixed in...dad's whole family pretty much have persistent malayalam vocab to this day....causing much amusement for say my mom (she thought their word for coconut oil was castor oil, when she was new to that vocab for example...joked about a lot still)
This variant runs inside my family esp among elders....Cheras were very strong in my ancestral area during the formative times in my ancestral family tree I would think.