How to use USD wallet if RAPYD doesnt support a particular currency?

RAPYD doesnt support MYR wallet but I need to allow payments in MYR.
Recommendation I received is to show hosted page in MYR and save funds in wallet in USD.
Again convert from USD to MYR during the payout.

Now the question is how to do it with API?
Am using /checkout to create a hosted page
and /payout to create a payout.

What parameters to use in these APIs to achieve this case?
I collect payments to one or more wallets during payment.

I triedrequested_currency but I dont want users to see they are paying in USD.
They should always see MYR

My request

{
    "amount": 300,
    "country": "MY",
    "currency": "USD",
    "requested_currency": "MYR",
    "expiration": 1623908254,
    "complete_payment_url": "htt---",
    "error_payment_url": "htt---",
    "cancel_checkout_url": "htt---",
    "payment_fees": {
        "transaction_fee": {
            "calc_type": "gross",
            "fee_type": "absolute",
            "value": 0
        }
    },
    "payment_fees_display": true,
    "merchant_reference_id": "7f09c435-8d42-4fc5-b677-e97fee3c820d",
    "ewallet": [
        {
            "ewallet": "ewallet_e9999757403347d43a5aa6d068f5d8a1",
            "amount": 10
        },
        {
            "ewallet": "ewallet_b99998215f54af4778e1f134b9d2fef",
            "amount": 280
        }
    ],
    "language": "en"
}