IIS reverse proxy with owncloud and keycloak backend - iis

Question

What I'm trying to achieve
I would like to create an IIS reverse proxy with hostname http://innerhub.domain.example/ and I would like to configure it to split the traffic as follows:
http://innerhub.domain.example/owncloud goes to http://192.168.0.192:8080/ as my owncloud service is hosting on that ip:port.
http://innerhub.domain.example/keyclkauth goes to http://192.168.0.192:8180/ as my keycloak service is hosting on that ip:port
Why I'm doing this
As owncloud documentation describes Owncloud's openID connect needs a reverse proxy so your IAPs can access the configuration under .well-known. So I figured I need to setup a reverse proxy between the owncloud and the keycloak in order to rewrite the .well-known url. It would work fine, but in order so owncloud redirects me to the correct url too I need to be able to access keycloak url too from the innerhub. So basically innerhub needs to split and rewrite urls between these two sites.
This is the network graph
What works so far
The url rewrite rules are working and I can reach the apps with http://innerhub.domain.example/*
Where am I stuck
Owncloud and keycloak too has response.redirect messages and I can't find a way to properly handle this in IIS. When owncloud redirects I get a new url: http://innerhub.domain.example/login and obviously it returns a 404, because this should be http://innerhub.domain.example/owncloud/login
My configuration file
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<system.webServer>
<rewrite>
<rules>
<clear />
<rule name="KeyCloak" stopProcessing="true">
<match url="^/?keyclkauth/(.*)" />
<action type="Rewrite" url="http://192.168.0.192:8180/{R:1}" />
<serverVariables>
<set name="HTTP_X_ORIGINAL_ACCEPT_ENCODING" value="{HTTP_ACCEPT_ENCODING}" />
<set name="HTTP_ACCEPT_ENCODING" value="" />
<set name="HTTP_X_FORWARDED_HOST" value="{HTTP_HOST}" />
<set name="HTTP_X_FORWARDED_SCHEMA" value="http" />
<set name="HTTP_X_FORWARDED_PROTO" value="http" />
</serverVariables>
</rule>
<rule name="OwnCloudAuth" stopProcessing="true">
<match url="^/?owncloud/\.well-known/openid-configuration" />
<conditions logicalGrouping="MatchAll" trackAllCaptures="false" />
<serverVariables>
<set name="HTTP_X_ORIGINAL_ACCEPT_ENCODING" value="{HTTP_ACCEPT_ENCODING}" />
<set name="HTTP_ACCEPT_ENCODING" value="" />
</serverVariables>
<action type="Rewrite" url="http://192.168.0.192:8080/index.php/apps/openidconnect/config" logRewrittenUrl="true" />
</rule>
<rule name="OwnCloud" stopProcessing="true">
<match url="^/?owncloud/?(.*)" />
<serverVariables>
<set name="HTTP_X_ORIGINAL_ACCEPT_ENCODING" value="{HTTP_ACCEPT_ENCODING}" />
<set name="HTTP_ACCEPT_ENCODING" value="" />
<set name="HTTP_X_FORWARDED_HOST" value="{HTTP_HOST}" />
<set name="HTTP_X_FORWARDED_SCHEMA" value="http" />
<set name="HTTP_X_FORWARDED_PROTO" value="http" />
</serverVariables>
<action type="Rewrite" url="http://192.168.0.192:8080/{R:1}" />
</rule>
</rules>
<allowedServerVariables>
<add name="HTTP_X_FORWARDED_HOST" />
<add name="HTTP_X_FORWARDED_SCHEMA" />
<add name="HTTP_X_FORWARDED_PROTO" />
<add name="From_where" />
</allowedServerVariables>
<outboundRules>
<clear />
<rule name="KeyCloak" preCondition="ResponseIsHtml1">
<match filterByTags="A, Form, Link" pattern="^http(s)?://192.168.0.192:8180/(.*)" />
<conditions logicalGrouping="MatchAll" trackAllCaptures="true" />
<action type="Rewrite" value="http://innerhub.domain.example/keyclkauth/{R:2}" />
</rule>
<rule name="OwnCloudAuth" preCondition="ResponseIsHtml1" enabled="true" patternSyntax="ExactMatch" stopProcessing="false">
<match filterByTags="A, Form, Link" pattern="http://192.168.0.192:8080/index.php/apps/openidconnect/config" />
<conditions logicalGrouping="MatchAll" trackAllCaptures="true" />
<action type="Rewrite" value="http://innerhub.domain.example/owncloud/.well-known/openid-configuration" />
</rule>
<rule name="OwnCloud" preCondition="ResponseIsHtml1" stopProcessing="false">
<match filterByTags="A, Form, Link" pattern="^http(s)?://192.168.0.192:8080/(.*)" />
<conditions logicalGrouping="MatchAll" trackAllCaptures="true" />
<action type="Rewrite" value="http://innerhub.domain.example/owncloud/{R:2}" />
</rule>
<rule name="RestoreAcceptEncoding" preCondition="NeedsRestoringAcceptEncoding">
<match serverVariable="HTTP_ACCEPT_ENCODING" pattern="^(.*)" />
<conditions logicalGrouping="MatchAll" trackAllCaptures="true" />
<action type="Rewrite" value="{HTTP_X_ORIGINAL_ACCEPT_ENCODING}" />
</rule>
<preConditions>
<preCondition name="ResponseIsHtml1">
<add input="{RESPONSE_CONTENT_TYPE}" pattern="^text/html" />
</preCondition>
<preCondition name="NeedsRestoringAcceptEncoding">
<add input="{HTTP_X_ORIGINAL_ACCEPT_ENCODING}" pattern=".+" />
</preCondition>
<preCondition name="isStatus">
<add input="{RESPONSE_STATUS}" pattern="3[0-9][0-9]" />
</preCondition>
<preCondition name="x-forwarded-KeyCloak">
<add input="{HTTP_X_FORWARDED_HOST}" pattern="http://innerhub.domain.example/keyclkauth/.*" />
</preCondition>
<preCondition name="x-forwarded-OwnCloud">
<add input="{HTTP_X_FORWARDED_HOST}" pattern="http://innerhub.domain.example/owncloud/.*" />
</preCondition>
</preConditions>
</outboundRules>
</rewrite>
</system.webServer>
</configuration>