shiny-server - Websocket 404 Apache2 / Debian

I'm trying to host a Shiny app in our cloud infrastructure and running into websocket 404 issue. I closely followed the community to implement the proxy pass and fixed the graying out screen issue. But I still see errors in our server logs after starting the application. Please find below the apache2 config and server logs,

Config:
ProxyPassMatch ^/(.+)/websocket wss://127.0.0.1:3838/$1/websocket
ProxyPassMatch "/sockjs(.*)" "http://127.0.0.1:3838/sockjs$1" keepalive=On
ProxyPass /count http://localhost:3838/sample-apps/count/ ttl=120
ProxyPassReverse /count http://localhost:3838/sample-apps/count/ ttl=120
RewriteEngine On

RewriteCond %{HTTP:Upgrade} =websocket
RewriteRule /(.*) wss://localhost:3838/$1 [P,L]

Server logs
[2019-11-05 15:26:42.494] [TRACE] shiny-server - Reusing existing instance
[2019-11-05 15:26:42.495] [TRACE] shiny-server - Worker #1248ef285b5ca0bc acquiring http port. 1 HTTP, 0 WebSocket, 2 pending.
[2019-11-05 15:26:42.495] [TRACE] shiny-server - Worker #1248ef285b5ca0bc acquiring pending port. 1 HTTP, 0 WebSocket, 3 pending.
[2019-11-05 15:26:42.495] [TRACE] shiny-server - Proxying request: /
[2019-11-05 15:26:42.495] [TRACE] shiny-server - http_proxy event: start
[2019-11-05 15:26:42.495] [TRACE] shiny-server - http_proxy event: proxyReq
[2019-11-05 15:26:42.559] [TRACE] shiny-server - http_proxy event: proxyRes
[2019-11-05 15:26:42.559] [TRACE] shiny-server - http_proxy event: end
[2019-11-05 15:26:42.560] [TRACE] shiny-server - Worker #1248ef285b5ca0bc releasing http port. 0 HTTP, 0 WebSocket, 3 pending.
[2019-11-05 15:26:43.440] [DEBUG] shiny-server - Creating a new robust connection: bpdHGNvRNkRQJhxgej
[2019-11-05 15:26:43.611] [TRACE] shiny-server - Accepted SockJS connection for /count
[2019-11-05 15:26:43.615] [ERROR] shiny-server - Websocket 404: /count
[2019-11-05 15:26:49.497] [TRACE] shiny-server - Worker #1248ef285b5ca0bc pending session timer expired
[2019-11-05 15:26:49.497] [TRACE] shiny-server - Worker #1248ef285b5ca0bc releasing pending port. 0 HTTP, 0 WebSocket, 2 pending.

Could someone help me in this regard

Thank you