Dex wins this. Honestly he'd probably kill Curtis with a billy club to the throat before Curtis could even go for the T-Spheres, Curtis basically has no speed feats while Dex was able to kill/disarm fodder before they could even react.
Gif 1: Disassembles his gun and skewers 2 Albanians with it before they could even react.
Gif 2: Disarms 2 FBI agent before they could even react.
Hypothetically speaking even if Curtis were able to throw his T-Spheres Dex could always just knock them out of the air, Anatoly did it and Dex is far more accurate than him.