Set an improbable target of 529 runs for an outright win, South Zone were bowled out for 234 in 71.2 overs.
The opener remains unbeaten on 209 as West extended the lead to 319 at stumps on day three.
The left-handed Jaiswal, who stared with a fine 68 in Royals' six-wicket win over Punjab Kings, received a bat from Sanju.
Following their seven-wicket loss to RCB, several Royals youngsters, including Jaiswal, had a long conversation with Kohli.
India suffered a collapse as they lost their last seven wickets for just 21 runs.
India, who walloped Pakistan by 10 wickets in the semifinal, will be playing their seventh final as opposed to Bangladesh playing their maiden final.
Leg-spinner Ravi Bishnoi scalped 4/5. India romped home in just 4.5 overs to notch up their second successive win.
Playing in his debut Vijay Hazare season, the 17-year-old scored 203 off 154 balls, which included 12 sixes and 17 fours against a Jharkhand attack that included out-of-favour India pacer Varun Aaron and Shahbaz Nadeem.