The style of architecture, perhaps?
Maybe. Though the only thing they really mention is "The surviving temples are dedicated to many different deities, making it unusual among temples of that period" - suggesting it doesn't fit.
These ruins are located at the eastern side of the 'tip' of India. On the western side, in the Gulf of Khambhat there have also been some amazing underwater ruins discovered. These are located at "20-40m water depths, at a distance of about 20 km from the present day coast."
All dating methods, including comparison of architecture and carbon dating of wood, haven't reached conclusions because no-one agrees. They tested the piece of wood three times. When all three tests said somewhere around 9000-9500 years old they dismissed it because the site couldn't possibly be that old. Wood had to be unrelated.
I'm just very skeptical when they casually mention "about 1,100 to 1,500 years old". And have to claim some local phenomenon caused the land to sink. Sea levels did rise tremendously and can explain all underwater ruins worldwide very logically, one only needs to push the date back.