I still think India needs a spinner like Ashwin in ODI's. Chahal is good in T20's and Kuldeep in Tests as a backup but Ashwin and Jadeja combo in ODI's will be lethal.
For the 3rd ODI India must opt Chahal for sure ahead of Kuldeep and they really need a 6th bowler. Playing with 5 bowlers is not suited to India.
They had the 6th bowler in Hardik Pandya, but he couldn't bowl due to injury. And that was the reason why the Indian captain was overdependent on Krunal Pandya and Kuldeep Yadav, despite they being expensive. I don't know whether Chahal is the right choice here. He is a wicket taking bowler, but his economy rate is not good. Given the fact that the England batsmen are in good form, I won't be surprised if he goes for 7-8 runs per over.
I think Hardik Pandya recovered from that injury and he even bowled few days back in the T20 matches but not bowling on ODI is the real question. He may not be completely fit to bowl 10 overs but bowling 5 overs is enough for the 6th bowler.
And for the 3rd ODI, Chahal was in for sure in my opinion because there is no other better bowler for spin in the squad right now.