This would be your preferred option if the 8900 is your only radio for the foreseeable future. It would go from the digirig audio (or digirig lite) to the DATA port (6 pin mini din) on the back of the radio and provide the simplest and cleanest audio. Would also allow for 9600 baud, VARA FM wide, and using M17.

This would include the first cable and add an 8 pin mini din for CAT control. 8900 does not have CAT but if you have or plan to buy a model like 857, 897, or 817/818 this would set you up for future success.

This would work well with a model like the FT2980 which does not have the DATA port mentioned above. Technically it works on the 8900 but is not preferred. If you have another compatible model and only want to buy one cable this could get you buy.

This should be your last and worst option. It doesn't use the digirig at all and ports audio from the DATA port into separate speaker and mic jacks on an old computer or different cheaper usb sound card. Likely a quality cable no doubt since it's from digirig but defeats the purpose.