I have done this method twice and worked in less than an hour for me, maybe even like 30 mins.
Make sure hours are 11am to 4pm on days without events or rain preferably.
1- I talk to every villager except target villager for 3-4 times and completely ignore undesired villager. However, after talking to all of the rest, I hit the target with a net (I was avoiding this and actually I feel so bad lol but I was getting desperate with other methods) I hit them until they are sad
2- Then save and quit and add 15 days.
There should be a villager wanting to move out. Both times I've done this is not the target, so I repeat the first two steps
3- After I've done this twice the target villager has asked to leave without fail!
Let me know if you try this and it worked!