Note the following from the Description:

In some cases, there may be multiple reasons for denying or detaining an entrant. For this exercise, you will only need to provide one reason.

It may be possible that the reason for denial given is just one of multiple reasons for denial. But it's also possible that you may have mixed up which documents pertain to which entrants during debugging. I'd suggest tweaking your debugging code to ensure the latter is not the case.

"A "worker" is a foreigner entrant who has WORK listed as their purpose on their access permit"

However if an entrant doesn't have an access_permit then how can they be categorised as a worker?

I am failing a test case where bulletin -> "Workers require work_pass" and one entrant has no access permit or a work pass. How else can I categorise him as a worker if he doesn't have a access permit to begin with?

I don't understand how the Kata ratings work but I've seen 4Kyu ones harder than this.

Probably it has been fixed or it was you mutating the input

I agree. The kata ranking on this website seems to be quite arbitrary.

If you attempt the code without a working solution it will give you the input strings for the failed test cases

To me it's quite clear.

Pop y,x, and v -> stack[-1] =y, stack[-2] = x, stack [-3] = v.

Once you have popped your y,x,v values, you can reference grid[x][y] using those values.

Really fun Kata! Took a while to work through but learned a few things along the way.

Sadly couldn't submit final solution as I was using match case (Python 3.10) which is not supported on Codewars. Will rewrite the code one day but for now glad to be done with this kata!

for 1, raising an error is part of the criteria, but I agree with everything else

I am both delighted and frustrated by this kata after completing it in Python.
I am glad I found one fast solution myself and a number of slow ones.
I am glad that I learnt that in Python positive and negative power notations have dramatically different performance, that Py integers do not have precision and that things like float128 are platform-dependent fiction.
I am glad that I have gone through numPy docs and now understand what it is and how to use it (and even solved with it), as well as that even numPy may have a super-counterintuitive location of a seemingly super-necessary functionality.
And I am terribly frustrated that in the end I see the solutions out there that just should not be passing by timeout, it's basically my slow code ignoring all the above, which I just cannot explain.
Very enlightening task.
I do not mar it as spoiler, though this one has some hints.

I wish I could pretend to understand this!

Can I safely skip this kata?

Yes. Pick any kata you want from the list, not the ones you get recommended.

Can I safely skip this kata?

I am on Codewars to help develop my programming skills and have no intention of going into mathematics. I'm not sure what this kata is teaching other than to write out a mathematical function?