Hi Sruthi,
With the medical insurance being paid out by the insurer, on this front this should not create any losses for the employer, if the employee claims the full medical insurance limit before the last working day.
But them if it is a case where the employer at the begining pays the full year's premium to the insurer or TPA and then deducts the amount on a monthly basis from the employee payroll, then this is seen as a concern, if the employee exits early, because with a payout already done, the excess paid premium cannot be refunded from the insurer.
So, unless the employee had been made aware at the beginning that his full year's insurance premium would be recovered if he exits early after making a successful insurance claim payout, nothing can be done.