MS Office Online Integration (SSL) with Nextcloud 22.2.0

Hi Nextcloud Community,

I need some help interconnect a Server Nextcloud(NC) with a Server Microsoft Online Office (MOO).

In the followings I will describe the specs of the NC and MOO servers.

NC server specs are:

-version 22.2
-system operation CentOS 8
-database MariaDB version 10.3
-apache version 2.4.37

MOO server specs are:

-system operation Windows server 2012 R2 version 6.3
-64 bit machine
-licensed

Pics link:

https://drive.google.com/drive/folders/1JN4HupayB1SKjvcYihwBmzLlOQNj9hGu?usp=sharing

I’ve tested locally MOO and it’s functional as seen in the google drive link. (nextcloud6 – discovery; nextcloud7 – link generator; nextcloud5 – link test)

Both servers are connected in a close wired network behind Proxy and Reverseproxy servers.

I’ve deactivate and uninstall from the web interface apps OnlyOffice, Online Office and WOPI, then I fresh installed only for MOO, with all these some settings are taken automatically (probably from the database).

What should I delete without affecting other NC functions to be sure that wont bring back the old settings?

What is the difference between apps Office Online Integration and WOPI? Which one should I use/install in such server-infrastructure?

I don’t have code errors in NC logging or server logs, but seems that the settings tab from NC is not loading when I activate Office Online Integration app, as shown in pics. (nextcloud14 ; nextcloud3.1)

When I activate WOPI app seems to not working as intended, shown in pics. (nextcloud3 ; nextcloud11 ; nextcloud12 ; nextcloud13)

Thanks in advance!