Apache2 rewrite rules not being picked up - mod-rewrite

Question

I've a domain which is using 2 separate virtualhost files: one for :80 and one for :443
The :80 setup is pretty easy, it's only job is to redirect to :443:
<VirtualHost *:80>
# This is the first host so it's the default.
# So although I've specified a ServerName and ServerAlias anything else not specified elsewhere will also end up here.
ServerName www.domain.com
ServerAlias domain.com
ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined
# Redirect everything to https:
RewriteEngine on
RewriteRule ^(.*)$ https://www.domain.com$1 [R=301,L]
</VirtualHost>
The :443 simply needs to add www to the beginning of the url if it was absent:
<VirtualHost *:443>
# This is the first host so it's the default.
# So although I've specified a ServerName and ServerAlias anything else not specified elsewhere will also end up here.
ServerName www.domain.com
ServerAlias domain.com
ErrorLog ${APACHE_LOG_DIR}/ssl.error.log
CustomLog ${APACHE_LOG_DIR}/ssl.access.log combined
# Redirect everything which is not already on the real www domain name to that:
RewriteEngine on
RewriteCond %{HTTP_HOST} !www.domain.com
RewriteRule ^(.*)$ https://www.domain.com$1 [R=301]
ErrorDocument 404 /404.html
</VirtualHost>
I've 1 case in which these Rewrites seem to fail:
https://domain.com -> should point to https://www.domain.com but it points to https://www.domain.com%24/# . Obviously the characters at the back prevent the DNS server from finding the domain.
What is causing this issue? I've already had helped creating these virtualhosts files but it seems they're still not fully working as expected.
BUT I also want to rewrite my URLs to nicer ones. I think my rule is correct and the Rewrite block in :443 looks like the following
RewriteEngine on
RewriteCond %{HTTP_HOST} !www.domain.com
RewriteRule ^(.*)$ https://www.domain.com$1 [R=301]
RewriteRule ^subpage/(.+)/?$ subpage.html?$1 [NC]
Which should rewrite
https://www.domain.com/subpage/2 -> https://www.domain.com/subpage.html?2 but it's just pointing towards my 404 file now.
It might be something obvious, but I'm not seeing my mistake.

Answer 1

NOTE: This doesn't solve the problem as stated here, but it does solve the underlying problem.
As this is a production environment (how awkward.) my webserver, which was pretty weak to start with, got flooded rather quickly. My company greatly increased my budget (we were expecting a lot of traffic, but were hoping it would build up slowly which it didn't) so I was able to set up multiple servers and placed 2 HAProxy loadbalancers in front of them. I used the HAProxy configuration to solve my problems using:
frontend http
bind MY_IP:80
redirect prefix http://www.domain.com code 301 if { hdr(host) -i domain.com }
redirect scheme https code 301 if !{ ssl_fc }
frontend https
bind MY_IP:443 ssl crt /etc/haproxy/certs/domain.com.pem
redirect prefix https://www.domain.com code 301 if { hdr(host) -i domain.com }
reqadd X-Forwarded-Proto:\ https
default_backend app_pool
backend app_pool
balance roundrobin
redirect scheme https if !{ ssl_fc }
server app-1 MY_IP:80 check
server app-2 MY_IP:80 check
server app-3 MY_IP:80 check
server app-4 MY_IP:80 check
which will always redirect to the www.domain.com version and enforce HTTPS as well. Setting this up in HAProxy is way easier than using VirtualHost in my opinion.