Will Marketo Sales Insight Emails Be Sent If Marketing Suspended Is Set to True?

When Marketing Suspended is checked in a lead's record, it will prevent any non-operational email from being sent by Marketo, including the emails sent from Marketo Sales Insight in Salesforce, which are routed through the Marketo infrastructure.

Sales Insight for Outlook or Gmail emails however, are not sent via Marketo. They are sent by the mailserver to which the client is connected; ie Google mail servers or Microsoft Exchange Servers, and are not under Marketo's control.