Biult-In CODE server - permission denied

Nextcloud version 19.0.5:
CentOS 7.8
Apache 2.4.6
PHP 7.3.24

Trying to run Collabora with built-in CODE server.
Collabora Online 3.7.9
Collabora Online Built-in CODE server 6.4.14

But - dot is red.
“Could not establish connection to the Collabora Online server.”

In apache log I can see
sh […]apps/richdocuments/collabora/Collabora_Online.Appimage: permission denied
apps/richdocuments/collabora/Collabora_Online.Appimage has permissions: 744, and belongs to correct apache user (apache).

No entries in NC logs.

Tried to run it manually and - as apache or root user I can see:

/tmp/.mount_CollabxdxIPV/AppRun: line 14: warning: setlocale: LC_ALL: cannot change locale (C.UTF-8)
loolwsd: /lib64/libstdc++.so.6: version GLIBCXX_3.4.20' not found (required by loolwsd) loolwsd: /lib64/libstdc++.so.6: version GLIBCXX_3.4.21’ not found (required by loolwsd)
loolwsd: /lib64/libstdc++.so.6: version `CXXABI_1.3.9’ not found (required by loolwsd)

As diffrenet users - Permission denied.
So, looks, that there is reallly permission issue, but even changing file permissions to 777 didn’t help.

How to work on this issue?

And another thing - should I try to do something with above loolwsd errors, or they are only because I’ve tried to run appimgae from commandline (on server without any GUI)?

I have the same problem, but with litle diffrent enviroment:
Nextcloud 20.0.2
Collabora Online - Built-in CODE Server
6.4.14
CentOS Linux release 7.9.2009 (Core)
httpd-2.4.6-97.el7.centos.x86_64
php-7.4.13-1.el7.remi.x86_64

In log:
/tmp/.mount_Collabjze1Mo/AppRun: line 14: warning: setlocale: LC_ALL: cannot change locale (C.UTF-8): No such file or directory
/tmp/.mount_Collabjze1Mo/AppRun: line 14: warning: setlocale: LC_ALL: cannot change locale (C.UTF-8)
loolwsd: /lib64/libstdc++.so.6: version GLIBCXX_3.4.20' not found (required by loolwsd) loolwsd: /lib64/libstdc++.so.6: version GLIBCXX_3.4.21’ not found (required by loolwsd)
loolwsd: /lib64/libstdc++.so.6: version `CXXABI_1.3.9’ not found (required by loolwsd)

fontconfig-2.13.0-4.3.el7.x86_64