crefwatch:

 

But it now seems clear that even though the rollover was within TIAA-CREF, I gave up my vintages in TIAA Traditional.

In any case, it's next to impossible to verify any of this, because your statements don't break out holdings and income by vintage. 

Would be surprised if you gave up your vintages.  Think you could still verify this as T/C will give you the amounts you have in each vintage with a phone call.  You should have some funds in the vintages prior to your rollover date. 

Around 1999 I converted a SRA to Roth status.

I'm sure I retained all prior vintages, since in 2000 I noticed that all prior vintages in my Roth were less than that of the 2000 vintage.  Thus, I made my first flip at that time.

Dick