How to find which landline wires are mine using sensors on my cell phone?
The only thing that I can think of to do without using a line-mans phone is to bring a telephone to that jumble and connect it to each line one at a time and call the number that reads back the line number. I don't know what it is in your area or provider, but there should be a 3 digit number you can dial on any landline and it will read back the number of the line to you.