Order from admin page link “customer payment page” issue

Orders made via normal checkout work fine. But an order is created / received as “payment pending” status, when we send the customer the link, currency passed to payment gateway is set to whatever currency the last order on checkout was.

For example, if the order was made in USD (let’s say they have Widget for $29.99 USD), but the last order via normal checkout was in EUR, when customer goes to payment page (ie, Paypal), the value is set to EUR instead of USD. So on the Paypal page, they will see ‘Widget 29.99 EUR’ and be charged in euros.

How can we ensure the correct currency gets passed to the payment gateway when collecting payment via the “example.com/checkout/order-pay/[orderId]/?pay_for_order=true&key=[key]” endpoint?