Hello accounts-2upc-co,

Nice to see you in the Community! Okay, let's go ahead and perform these steps because I believe this is more of what you need to remove the pay button on the email invoices. 

To change the payment options on an existing invoice:
 

1. Go to Get paid & pay or Sales, then select Invoices 
2. Locate the invoice you want to update, then select Edit ✎.
3. In the Online payments section, choose Edit.
4. Select the payment options you want.
5. Click OK.
6. Hit Save or Save and close.

 To change the invoice payment options with new invoicing:
 

1. Go to Get paid & pay or Sales, then select Invoices.
2. Find the invoice you want to update, then select Edit ✎.
3. Select Payment methods.
4. Turn the switches on or off for the payment method you want to use.
5. Choose Save or Save and close.

In your case, you can then deselect some or all the payment options you do not need. For more information about processing payments in QuickBooks Online with QuickBooks Payments, this article is very instrumental! Let me know if you have any other questions! I will be more than happy to assist! Take care for now.