Rick, are you sure that both records were not his? If you look at the length of service deducted from the year discharged they end up the same: c.1790 as the year of enlistment.
I think it certainly would be worth your while to have a look at WO 121/60/191 where the records look far more informative than the second one.

Regarding the microfilm image being cut off, the Nat Archives used to let people look at the original documents if the film was unreadable or badly filmed. No doubt you tried asking for these? They might need notification a few days in advance to obtain them from storage.

Sue