So for now you have sellers only in SA, so you only need to solve remittance there? PayPal is expensive (2%) but it will work. Wells Fargo supports FX Wire into South Africa, and I think HyperWallet may support SA.
As for escrow, depending how you structure your marketplace, you might not need to do it this way. If you're selling services, could you subcontract your guides? If you're just paying your contractors, then it's not payment. Of if you're selling digital goods, could you take inventory and then resell it as an e-tailer? e-commerce is not payment.
As for PCI compliance, you're already using Stripe - I assume with a token implementation - so you're not seeing the credit cards anyway. You bill your customers, take the money, and turn around and pay your vendors to fulfill your promise to the customer. Of you could use PP chained payments but there is complexity there.
$10 ticket size is...small. It costs at least a few bucks just to get a payment from the US into SA.