resque-web | This is an extraction of Resque-web from inside Resque

I have my rails application that has a job (using Active Job). I use resque and resque-scheduler gems for queuing backend.

I want to connect my rails application to a redis-to-go server with Resque on Heroku but I get many error messages on my logs, like this:

We have two Rails applications using Resque and Redis. Resque and Redis are configured identically on both apps, which are both using Rails 4.2 and Resque 1.27.4.

However, the availability of Resque server at the /resque path is best described as "uneven" across the two applications (I'll shorten their real names to "planning" and "staffing" for simplification).

• Both sites work fine in production (on Heroku). This is particularly interesting because the current production deploy of "planning" has older versions of Rails and Resque than "staffing" - my current project is bringing it up to date.
• In staging, "staffing" works fine; "planning" returns a 404 error. (Airbrake doesn't log an error.) When jobs are sent to Resque, they seem to run; we just can't see the server to see the queue.
• In development (my local environment), using rails s, both applications raise a Routing error: No route matches [GET] "/resque", even though the list of routes which follows on the error page includes /resque at top priority:

resque_server_path /resque Resque::Server

Where do I start figuring out what's going right in one place and wrong in another?

Here's the relevant routes.rb line (all of these are the same in both apps):

I need to initialise rails from an arbitrary script so that I can access some ActiveRecord objects using Clockwork

UPDATE: The issue only occurs when require 'clockwork' and require_relative './config/environment' are both required.

They recommend initializing it like this: