There is one extra action required if you want to see the data from this source in ROI Hunter. To track assisted conversions, your ads need to have their utm_content UTM tag set to {{roihunter_id}}. You can edit your UTM parameters directly from the Dashboard - each Virtual Account has its own settings. Click on ⚙ next to the name of your Virtual account and select the UTM Params and GA profile option.
Be aware the ads created before your changes in UTM Params and GA profile settings are not affected by this change - only new ads will have these settings applied. However, you can still edit UTM Parameters of your already existing ads thanks to the Edit Ads feature available in the Campaign manager.
Then you are ready to see the data on the Dashboard and in the Campaign Manager as well. All you need to do is just to add the particular columns.
To know more about Multi-Channel Funnels, read the perfect explanation here from the Google Analytics team directly.
source: Google Analytics YouTube channel