Select rows of 2 different models to do an action

Selecting the account is the easy part (As Matt has described above).  Capturing the array of services selected and passing them through to your email tool (along with the Account)  will be more challenging.  Zach has written a post about passing multiple items selected to a third party email service.  https://community.skuid.com/t/how-to-add-marketo-send-email-mass-action-to-a-skuid-tab…

I think your mass action could start by opening a popup that captures account, and then the popup has a “next button”  that passed the Account and  the array of selected service items as described in Zach’s link.