updated thread topic to 889-ZZB.
that model is a 22 stop fruit machine for the silver city casino. It uses the same reel tapes, reel wiper boards, payout counter, top glass and reel glass as the 889-C model which I have some paperwork for.
below is your relay pic downsized and brightened a bit. The blue wire looks like the 6V power wire. Can't really see what wire colors are on the switches on the relay.
there's a couple possibilities:
1] someone added the relay and it never had a coil. If you manually hold down the armature to move the switches, the jackpot numbers may change
2] it was something unique for the silver city casino and would only be on their schematic (drawing w-1046-1654)
3] it's on the 889-C schem, but without knowing wire colors that went to the coil or most/all of the colors on the switches, can't identify it
you're probably going to need to reverse-engineer it. if there was a coil and there's a solid orange 70 wire around there that could of attached to it, then the coil would be the same as relays in the upper compartment.
I'd draw a diagram of the relay of take more pictures identifying all the wires to the thing, and follow those wires to see what they are attached to as best you can. Then some guesses can be made on what the purpose of the thing is.