Hello,I am Pete, and I'll be happy to assist with your question today.
Did the ground shift during the landslide at all?
Can you test the phone line between the house an the opener for continuity, or run in a temporary phone wire to see if it operates again?
Some phone wire should be all you need for now. I suspect it is broken and running in some new wire will help prove this.
Any standard telephone cable will work just fine.
I'm not sure what wire was used for it originally but yes it should be.
Cat 5 wire and phone wire are quite similar.
You can also use Cat 5 wire for this opener system.
Sorry for the delay in getting back to you - I was offline for a while.
I didn't get any photo from you - can you attach it on your question page here?
Can you use the new wire to replace the old wiring?