How to check if a directory exists using .htaccess?

Question

htaccess

Given.

1. Hosting nginx + apache 2.2.4
   
2. Subdomain, this is important. %{DOCUMENT_ROOT} works "not correctly" in it; it gives the path to the main domain folder. t.wakh.ru (otherwise, the option with the wakh.ru/t subfolder did not work either).
   
3. Files to check:
   
   • /1.html
     
   • /1.shtml
     
   • /d1/2.html
     
4. .htaccess with the following content
   

   AddHandler server-parsed .shtml
   
   Options -Indexes +FollowSymLinks +Includes
   RewriteEngine On 
   #RewriteOptions Inherit
   RewriteBase /
   
   RewriteCond %{REQUEST_FILENAME}	(([^\/]+\/)*[^.]+)\.html
   RewriteCond %1.html 	!-f
   RewriteRule ^ 		1.shtml	[QSA,L,E=VARR:er]

   
   

Problem:

• when requesting t.wakh.ru/d1/2.html, the redirect does not occur, the file /d1/2.html exists - everything is correct
  
• when requesting t.wakh.ru/d1/1.html , a redirect occurs, because there is no /d1/1.html file - everything is correct
  
• when t.wakh.ru/d2/1.html is requested, the redirect does not occur, although there is no d2 directory, respectively, and the /d2/1.html file too - How to fix this?
  

Variant with

RewriteCond %{REQUEST_FILENAME}	(([^\/]+\/)*[^.]+)\.html
RewriteCond %2	 	!-d

didn't work.
I found out that RewriteCond %{REQUEST_FILENAME} (([^\/]+\/)*[^.]+)\.html does not work if there is no directory.
If you want to help, feel free to create a similar structure on your server / hosting, in the process of testing on mine, inadequate behavior arose and pressing F5 randomly produced different results.
And another question, in the process of testing, I wanted to use the env|E=[!]VAR[:VAL] flag, but it turns out to be an empty value. Why?
PS
My last question remained unanswered, probably due to confusion.

Answer 1

1. to make the root document work
2. in the nginx config, find if there is something about .htnl

location  ~* \.(html|htm)$ {
  error_page 404 /404.html;
  expires 30d;

3. all .htaccess to studio including CNC
4. what for RewriteCond %{REQUEST_FILENAME} ?
use RewriteCond %{REQUEST_URI}