Marketo can only create tasks for the Lead/Contact and not the Account.
One of my recommendations would be to have a "primary" and "secondary" flag on the lead/contact. So in this scenario the 2 most important leads, who would be the most relevant to speak based on the job title or any other important criteria, would be flagged as either the primary or secondary. Then when we create the task, our criteria would include that the primary and secondary records would be the only leads/contact records where the task was created and then the sales people can follow up with these leads/contacts.
Hope this helps
If you have a salesforce developer, ask them to try create an Apex class and trigger to "migrate" the task from the contact record to the parent account record
Hi, I'm assuming you are using Salesforce as your CRM so I would recommend doing this workflow through Salesforce. My company is also B2B and do most opp/product workflows off of the account and not the contact record so we definitely have most of our automated tasks set the way you want - for instance, if an opportunity isn't touched for a certain amount of time, it generates a task for the sales owner to reach out to the account (the sales team can decide who is best to contact). Your SFDC admin should be able to set this up for you.