Is it possible to use field values from a custom SFDC object, in an email?

I'm using the Salesforce-Marketo sync and I have a custom Salesforce object called "Agreement" being synced. The "Agreement" object is related to Leads, and it has several fields defined in it (see screenshot).

I can reference these fields when setting up a Campaign flow, which is great. It confirms that the values are present in Marketo.

I want to reference one of these fields in an email, namely "Agreement Name" using either a token or some other method.

But it seems like tokens are limited to only direct children of leads, for example: {{lead.First Name}}

The behaviour I am looking for is something like: {{lead.Agreement.Agreement Name}}

Hopefully this makes sense, and please let me know if it's possible to access this value in an email. It surely must be, as the information is clearly stored somewhere in Marketo.