Your question was originally closed for “needs more focus”, and each of these steps are concrete ways you can focus your question on the actual problem you are trying to solve.
Step 0: Interact with comments.
Usually, close voters will leave a comment explaining why the question was closed. Your question is no exception. All of the steps I am about to offer were in one form or another explained and asked about in comments under your original question. Comments are the primary means we use for quickly workshopping a question into something the stack is equipped to handle.
Step 1: Narrow the scope to the game you are playing.
In your question, you write (emphasis mine):
What rules exist in any edition to tabulate density of crowded groups in tight, pressing, forced or out-of-combat situations?
There are many editions of D&D. Unless you are currently playing games of every edition of D&D, you don’t need to know the squeezing rules for every edition of D&D. You should narrow the scope of the question to focus on the particular edition you are playing.
Step 2: Narrow the scope to a particular at-table scenario.
In your question you offer several different scenarios:
- Seven goblins in a snowfall, backed up to a tiny bluff. Whilst huddling up to a tiny fire they are hit by bon-firing / cantripping that hits a large number of them.
- Whilst thirty-three zombies cluster-reach through a portcullis a large urn of oil (above) pours & splashes down and is set ablaze.
- Three clumsy ogres slip-fall into a 10' cube-pit and seek to angrily push-throw one another out.
- A blue dragon (lightning: 'long and narrow') breathing on the crush of two phalanx groups clashing - how many are shocked?
At the same time, this is both too much, and too little information. Narrow the focus to one of these scenarios, the one that either has, or is most likely to, come up in actual gameplay, and give us more details about that one. These are all very different scenarios that will likely require unique judgments.
Step 3: Remove the requests for irrelevant answers.
This is Role Playing Games SE. We answer role playing questions with role playing experience. This means your question should be answered with two things: experience working with the written rules, or real at-table experience implementing house rules helpful to the situation. That’s it. Experience as a dance hall manager is entirely irrelevant. The only way such experience would be helpful in an answer would be something like:
Here’s what the rules say, here’s how I have ruled it in this real situation from my gaming table, and this seems consistent with my experience as a night club bouncer.
Real world experience can help to confirm or deny the intuition behind existing rules.
