What forms of payment can I use in Virunga?

Payments to Virunga National Park can be made by Credit Card and Bank payments. Cash payments are also allowed in USD (US Dollars), but one should ensure that the dollars are clean, not torn and not damaged (even a slight tear will not be accepted). Also, ensure that the dollars are not late than 2009 because Congolese Banks will not accept these old notes that are 2009 and back.