It would be better if you gave us more details about your service. At least, what kind of backlinks do you offer? It would save us a lot of time.
Are these links guaranteed to show up in searches? What is the success of your 5000 submission being indexed, do you have a percentage? Obviously 100% would mean 5000 backlinks would equal 500 indexed pages.
I will make sure at least 60%-70% of them are indexed, but google doesn't show all backlinks and it takes some time to show them in google search index.