Locating an elusive military record - researchers only please?

Question:

Locating an elusive military record - researchers only please?

James McKenna, Black Range Tales, an attack on woodcutters by Apaches in the Mimbres Valley, New Mexico. McKenna, gives the date as 'the fall of 1872. All ten wood cutters were killed, along with two troopers from Ft. Cummings, and someone named Young, who might, or mightn't have been military. McKenna describes him as 'a farrier'.

Eight microfilm of the records from the US Archives have provided hints that McKenna's dates might be wrong. That the attack might have been 1869, when a mail-carrier named Young was killed [farrier - carrier similarity might explain it]. Or it might be later, during the Victorio wars.

Muster rolls have been pesky, and thus far no reports of the deaths have emerged, though they ought to be in correspondence from Cummings.

A McGurk, Company C, 4th Regiment, under Captain Tucker, Fort Cummings, was one McKenna source.

1st microfilm order assumed Cummings rpts went to Craig. But most seems to be Leavenworth.

Any thoughts where to go next?

Additional Details

17 hours ago
Thus far haven't located McGurk, nor his unit, nor Captain Tucker. But there are a lot of gaps in the Cummings correspondence and reports. I need to find where else they might be located in the archives.

I'd like to do this by buying and searching microfilm, as opposed to hiring a private researcher in Washington.

Best Answer - Chosen by Asker: 17 hours ago
Thus far haven't located McGurk, nor his unit, nor Captain Tucker. But there are a lot of gaps in the Cummings correspondence and reports. I need to find where else they might be located in the archives.

I'd like to do this by buying and searching microfilm, as opposed to hiring a private researcher in Washington.