Two comments:
1. Didn't the IBM Executive typewriter require that you type each line twice in order to use the proportional font feature? Other have stated so. Seems very unlikely a typewriter like this would have been used for these documents.
2. Apples and apples. I don't think so. The physical size and spacing of Times Roman on a 1972 IBM typewriter and Microsoft Word just might be slightly different. If you lay a Word version over the top of the "1972" document you will see that size and spacing are IDENTICAL. That just seems very unlikely to me.
No.
I've already noted that. There are just too many threads going. By the way, the th is quite different in the word processor.