Because of the same-origin policy, which is enforced by browsers, BlueConic cannot 'see' into an iframe hosted on a different domain than the site that embeds the iframe. The best solution in this case is to place the BlueConic script in the iframe as well.
If placing the script in the iframe is not an option, you may want to try more creative solutions like creating a custom plugin and use an external library like the iframeTracker, which will provide you with ways to track clicks in an iframe. The possibilities however remain quite limited.