Specifying layout in namespaced controller

I am creating a new version of one of my controllers,

Original Controller:-

class ExampleController < ApplicationController
layout 'filename', only: [:method_name]
 ...
 def method_name
   #...some logic...
   respond_to do |format|
   format.html
   format.json {
     render json: {}, root: false
   }
   end
 end
...
end

New Controller:-

class V1::ExampleController < ApplicationController
layout 'filename', only: [:method_name]
...
 def method_name
   #...some logic...
   respond_to do |format|
   format.html
   format.json {
     render json: {}, root: false
   }
   end
 end
...
end

I keep getting error:-

Missing template v1/example/filename, application/filename with {:locale=>[:en], :formats=>[:html], :variants=>[], :handlers=>[:erb, :builder, :raw, :ruby, :coffee, :arb, :haml, :jbuilder]}

One of the solution is to create a folder structure v1/example and put my layout file there too. But I do not want to create duplicate copies of this file.

Another is to use a parent controller class of both new and old example_controller and specify layout there(and have a folder structure according to the name of the parent class). But this will be an overkill and also I plan on deleting old controller once all my clients migrate to new versions.

I also tried specifying like this:-

class V1::ExampleController < ApplicationController
layout 'example/filename', only: [:method_name]
...
end

but this also doesn't work.

How to tell my new controller to render layout from the old folder structure.