I ended up using the following workaround:
On IIS, in %System32%/inetsrv/config/applicationHost.config I added the following snippet at system.webServer/rewrite/globalRules/rule [name=ARR*]:
<severVariables>
<set name="HTTP_X_REMOTE_ADDR" value="{REMOTE_ADDR}" />
</severVariables>
Then I specified that name to the RemoteIpValve in Tomcat's server.xml
<Valve className="org.apache.catalina.valves.RemoteIpValve" remoteIpHeader="x-remote-addr" />
To use the newly added header instead of X-Forwarded-For