@KrisD15 Thank you for your reply!
Understood on using the refund amount from 1099G
The amount turbotax autofilled for "Payments and Withholding" was that of line 30 from my State return. This differs from my schedule A amount by ~$70
That said, the amount that was autofilled also appears earlier in my State return as "Colorado Tax Withheld, Payments, or Credits from your Colorado return" and turbotax's help section indicates most of the information for "Payments and Withholdings" can be found on my state refund.
So, It seems I should keep it as the original value TurboTax autofilled and only change the refund amount as you noted
