Adding Subscriptions Data to CRM, in Fields which can be used in Campaigns

Adding Subscriptions Data to CRM, in Fields which can be used in Campaigns

We are launching SaaS services. The products are built in Billing, they synchronise correctly to CRM, and can be created from CRM.

However, the data displayed in CRM about the subscriptions cannot be synchronized to Campaigns, which we need to manage messaging. It is instead displayed as shown in the attached file.

We have the added issue that one account or contact in CRM may have multiple subscriptions.

First, is there a way, using standard Zoho processes, to populate and keep refreshed subscriptions data in fields within CRM?

If not, how can it be done? I assume we would need to:
1) Create a subform for the Contact or Account for 'Subscriptions'
2) Create a Flow which transfers data from Billing to this Subform in CRM
3) Syncronise the data from the subform into Campaigns.

Please help!