It is. You are correct. “Th” just slightly higher. Weren’t some electric typewriters able to do a modified superscript?
Some were, but not in this case. The number set is just fancier that a set where all the number sat on the baseline. Having tails that extend on some numerals below the baseline is normal for this typeface. The 3, 4, 5, 7, and 9 have tails that reach below the base line of the font, just as the "p", "q" and "y" of the letter set does, although the numbers don't go quite as far. This makes the numbers look a bit fancier in combination. Look at the years, the serial number of the certificate, and anywhere else where the numbers are used together, and you will see that effect.