Ritz gives a 69.5 400 split and says the final time is 4:26.0 - so 65.5/4:05/8:11 average pace for the last 1200, at altitude. I don’t know if she can run 8:20, but 8:25 seems feasible.
Karissa Schweizer is currently the AR holder indoors at 8:25.70, which is #7 all time behind 6 Ethiopians. If hypothetically Monson ran 8:20i, that would put her #2 all time behind only Genzebe.
If she ran 8:20.00 outdoors that would make her #8 all time - but 4 of the 7 women under 8:20 are Chinese from September 12-13 1993, and one is Francine Niyonsaba. The “non Chinese” outdoor 3k record is Hassan’s 8:18.49. Klosterhalfen clocked 8:20.07 behind Hassan in that race in 2019.
I hope to see Monson make an all out attempt on Schweizer’s AR at Millrose, and it looks like that might be the game plan.