Short Plat requires neighbors help

[Curtis Bidwell]

I have 2 acres in the city (Puyallup, Wa) with an 1800sf SFR on one end of the property rented to the same family for 8 years. The city will allow me to divide into 3 additional lots.

I have an easement from the neighbor's property to the backside of my property but that does not qualify as access for development purposes.  The neighbor does not want me to develop behind him and so has stalled, declined help, etc...  I am looking for ideas to get him to do a lot line adjustment and trade him equal land so the easement becomes a legal access parcel (his side-yard for an extended back yard).   

Any ideas are greatly appreciated!