Maybe Max was wrong, and assuming, but apparently they hired the original crew to do a LOT of the script first, and made the decision to change casting later on? So it might not be a money thing.
I don't know that they had the original cast do "a lot" of the script. I would guess that they did Bombing Mission. Either way, it's obvious that they made a decision at some point between 2017 and now to completely overhaul the script and bring in new voice actors.
At the time, they were pretty much word-for-word recreating the original English game script. In general, the 2017 cutscenes are much closer to the original game in terms of pacing, staging, direction, and script.
In the current version, the dialogue is greatly expanded and far more natural, and the general tone is considerably more dynamic and thrilling, with more action and urgency.
I think it's probably safe to assume that a lot of the design choices changed around the time they cut CC2 loose, because combat has also clearly evolved since then, and the characters became more stylized and the lighting and colors more vivid.