Probably you have found this:
https://opencorporates.com/companies/us_pa/185910
Kenallen Coal Company, incorporated 1946, just in time for your paperwork.
Address was Greensburg PA (~20 miles ESE of PIttsburgh), the seat of Westmoreland County, which was a center of bituminous mining back in the day, and on the PRR main line I believe. Of course, that is probably the corporate office, not the mines or loading point, but it's a start.
JS
EDIT: Here is some wild speculation: I found a Google Book:
https://www.google.com/books/edition/In ... 22#f=false
from 1961, from the US Dept of Interior. Page 17 says the company address was 543 Locust Valley Rd, Greensburg, and they had beehive coking ovens in Carpentertown (which Google maps says is ~8 miles south of Greensburg) and Humphrey (there is a Humphrey St today in Greensburg). 543 Locust Valley Rd today on Google maps streetview is a modest house which could easily be that old - maybe Mr. Ken Allen ran his business out of his house.
I looked at the 1964 USGS topo - it shows a PRR line running N/S right next to Carpentertown (which is just ~ 2 streets) and an abandoned (already abandoned in 1964) spur going to a few buildings there. So there's a good chance that was the location of the coking plant. I guess you could go on PennPIlot and look at the aerial photos - not that I would recognize coking ovens if I saw them...
Can't find anything obvious quickly about where the Humphrey plant might have been.
What all of this has to do with the shipper, Distributors Fuel on the freight bill, I have no idea. Maybe they shipped from the Kenallen siding or spur?