So not to answer my own question, but I called Vanguard and found out the answer.
1. So Foreign Tax Income is NOT the amount in Box 1a, 1b, OR the sum. Do NOT use the amounts on the 1099-DIV to determine foreign income.
2. First, a correction. The amount on the "2019 Foreign Tax Paid" Form is not higher than the amounts on the 1099-DIV, it is slightly lower (at least for the fund that I was looking at). With that out of the way, you should use the Total Foreign Income identified on the "2019 Foreign Tax Paid" form. So this answer was confirmed with Vanguard. However, I think (but did not confirm) the reason for the difference between the 1099-Div and the "2019 Foreign Tax Paid" form is that not all of the dividends come from foreign companies. In my case about 98% of the dividends came from foreign companies, which is why Foreign Income is slightly lower on the "2019 Foreign Tax Paid" form than the amount listed in Box 1a of 1099-DIV.
I'm not sure of why QDI eligible foreign income is identified, but at least for my purposes it doesn't seem relevant.
TLDR: just use the info on "2019 Foreign Tax Paid" form. Ignore QDI eligible foreign income.
