To properly end this discussion, let me explain what I discovered ACTUALLY happened. My current money manager had my 401K source move the $50K to them as a direct 401K to 401K transfer. This is the reason there was no other distribution or tax information on the Source 1099-R. My current money manager then did the 401K to ROTH conversion internally, and generated another 1099-R from them properly indicating the $50K being taxable. However, they still left the box 16 (State Distribution) blank on their 1099-R (which I still think should have been populated but that's a separate issue).
I needed to enter BOTH of these 1099-R's into Turbotax to show the source of the funds (initial transfer) and the secondary ROTH conversion. When I entered the ROTH conversion 1099-R into Turbotax (using Step-By-Step), it automatically populated the State Distribution on the next screen with the $50K for state taxing purposes. (I did not "zero" that block in Turbotax to match the received 1099-R.) I believe this is the correct entry, and the resulting tax amounts come out to about what I expected.
Thanks again for your patience and help.
