Hey Casey,
I would look in the lead's activity log in Marketo. You should see an "Interesting Moment" activity for every "Click Link" you see in Sales Insight. In this activity log, you should also see if there are actually that many "Click Email" activities as there are interesting moments.
If the number of Click Email activities matches the number of Interesting Moments, you know that all these interesting moments are legitimate.
If there is a mismatch, I would investigate the campaign(s) that is creating the interesting moments to see what is going wrong.
Will