The cable end is a PL-259, an RF connector. Things like that are used for two-way radios, scanners, cellular telephones, etc. Consider it a bonus left you by the PO.

As for the hole, although the photo is a little too close-in (I'm not sure what I'm looking at), that may be where the blower is supposed to go. Is there a cable with a two-pin plug flopping around under there somewhere?

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970