A lot of people use Keyhole to track influencer campaigns. Here are step-by-step instructions on how to use Keyhole to track influencers.
Step 1) On your My Tracks page, click Advanced
This will take you to the Advanced tracker setup page, where you can specify more than just hashtags.
Step 2) On the New Tracking Campaign page, select "Specific users only"
In this case, you don't want to track all accounts using the hashtag, but just specific influencers. This option allows you to specify users for the tracker.
Step 3) Enter the influencers' account names to be tracked for each platform
For each platform (Twitter and Instagram) enter user account names separated by commas. The number of accounts permitted depends on the plan level you are on.
Also note that each platform's text box is only editable if the platform is selected in step 1.
Result: Only posts by specified influencers are captured
Only posts by specified influencers are captured in this Keyhole tracker. If you add influencers after your tracker has been set up, all future posts will be from those influencers but will not affect already collected data. If you set up the influencers before setting up the tracker, it will affect all posts collected within the tracker.