We are using Marketo Sales Insights in Salesforce to surface activities of prospects for our sales team. For a number of prospects that we are showing as having clicked to visit blog posts on our website, nothing shows up for those prospects under Web Activity. I've looked around the support forum and have seen that for some users the Web Activity pane is buggy in Google Chrome, but I do see Web Activity for many prospects in Chrome. Do people have to stay on the site for a certain amount of time for Marketo to register it as a visit?
Nope!
How are you proving that the prospects generated web activity (never mind MSI for the moment)? Do you see Visited Web Page in their Activity Log in the Marketo UI?