The original post goes back to 2013 as well as the first dozen or so responses. I can address what is currently going on in Namibia.
A few years ago the Namibian govt stopped banks from accepting traveler's cheques, US certified bank checks or money orders. The also made it illegal for Namibian citizens to exchange foreign currency for Namibian dollars. They did this to try and stop the black market exchange.
PH's will likely accept final payment in USD and if so, they likely have a friend with a foreign issued passport who will make the exchange for them, OR you'll have to make a stop at a bank or currency exchange office on the way home. Some, if you've pre-paid over 75% of your hunt costs upfront will let you wire the balance once you get home. Several options, just have to be sure to work the detials of final payment out with PH/Outfitter BEFORE you go.
Some do have CC machines and you can swipe your card to settle out your account. Down side of this could be that you CC company highlights your transaction as possible fraud and will send you an email or text message to confirm the transaction OR you'll have to call them. IF you don't have cell service this could result in your card being locked.
Taking cash is not as bad as you think. Generally, the riskiest part is between your house and the secure area of the airline terminals. The $10K limit is not really a limit. It is the limit that can be taken out without filling out a US Customs form that just declares the amount you're taking out. You only need to show the form if you are stopped at a US airport during the TSA screening.
Securing America's Borders
www.cbp.gov
Had a friend take over $35K out with him on a trip to Nam. Carried it in his carry-on backpack and had the form filled out. The bundle showed up on the TSA scan. He had the form wrapped around the bundle and he was waived thru by TSA when they did the physical check.