It seems that South Africa is enforcing strict regulations on importing vaping products, possibly due to health concerns or classification as dangerous goods. This could explain the return of your package and the hold-up in the US. You might want to check with local customs or the postal service...
It sounds like you’re getting a lot fewer puffs from your DD R compared to the Citadel, even with the Coolfire Z80's F0 and refresh functions. 900 puffs at 47W versus 2500 at 36W is quite a difference. Maybe the higher wattage is burning through the wicking faster, or it could be the difference...