1099-R taxable amount blank and box 2b taxable amount not determined is checked

The Total Distribution box is also checked.  This was a cash out of a universal life insurance policy.  The box 7 codes are 7 and D.  All other boxes are blank.

 

Through research of the policy history I have determined the taxable amount.  (policy purchased with after tax funds in excess of total premiums paid, a portion of the cash out is a reimbursement of those funds)  The policy was serviced by three different companies over the time that I owned it. Can I make an entry into box 2a in turbo tax if the 1099 is blank?