Your concerns about your clients being able to see your draft invoices have been heard, meaderiv. I'm here to assist you in any way I can to resolve it.
First off, could you please provide more details about the activity log you mentioned? Additionally, where can your client view the recurring invoice draft? Sharing this information would help us assist you better.
If you meant the Invoice activity in an invoice transaction, we can only see the statuses: Opened, Sent, Viewed, Paid, and Deposited. There's no option available to view invoice's draft.

However, if you meant something else, please don't hesitate to get back to this thread.
Lastly, you can refer to this article for guidance on how to handle failed recurring transactions in QBO: Fix failed recurring transactions in QuickBooks Online.
The Community team and I are always available to help you with any questions about recurring transactions. Click the Reply button, and we’ll provide detailed support.