Hello,
Not sure if you're still looking for ways to integrating Solarwinds with Servicenow. We have developed a solution and it can be used for free. It will be very simple to integrate Solarwinds alert to ServiceNow using our solution. You can read more about and download it at:
SolarWinds ServiceNow Integration | ServiceNow
Feel free to contact me for any questions: mjarjour@evanios.com