When we signed up for Market place Insurance, the broker told us that the money we withdraw early from a retirement account due to disability Will not count as income.
It's unfortunate you were told that.
Taxable retirement income counts as income, whether for IRS purposes or Obamacare purposes. So unless your retirement account is a Roth IRA, TurboTax must count your retirement income toward the calculation of the Premium Tax Credit and the amount you will repay.
When you take an early withdrawal from a qualified retirement plan or IRA due to total & permanent disability, you do not have to pay the early withdrawal penalty that would normally apply. But the taxable portion of the retirement income will still factor into Modified Adjusted Gross Income (MAGI), which is used for the Premium Tax Credit calculations.