Two ways I see to do it:

1. The part of the process they are completing just before and after this policy form would be two separate tasks, with the policy form being a third task in between them (with Gateways to determine whether or not to include it).
2. Manage the policy form as a separate process that can be acessed via URL.  Then using a Custom HTML element within your actual form (which can be shown/hidden via field rules), include a link to the policy form process:
   1. Example:
      <a href="https://answers.laserfiche.com" target="_blank">Click Here to Open Policy Form</a>  
   2. This is great for leaving the form they are working on in progress while they open and process the secondary form.
   3. The downside here, is that without some Javascript, you're not going to be able to require that they actually click the link to process the other form.  I am happy to help with the Javascript if you want to go this route - I have a similar form that I use, that is able to tell that the other process was actually opened and processed.