Can we 3d Print houses for Flood affected 300k people in Kerala India?

Yes. Lets say an average family is of 3 people so the total homes required will be around 100K.Also the 3D printed home takes around 24 hrs (1 day) to built. So let's say even 1K companies or 3d printers are working round the clock, then it would take around 100 days. so it will take quite long (3.5-4 mo) time. but its possible.

update: also it will be requiring a lot of funding or donation as 3d printers are costly and also the material and transportation cost will add up more to the cost.