I can't see any additional info in your log files.
Can you check if changes was successfully applied? (also please add this additional line)
<logger name="com.solarwinds.oncall.orion.logic.impl.SwisOrionApi" level="TRACE" />
AlertCentral uses port 17778 to communicate with ORION. Are you sure that ORION is able to listen to this port? (no firewalls or brandmauers).
What URL you use to access ORION from browser (http://host:8787/Orion).
Do you try to connect using this host value?