I also noticed that the third sample with Chinese sounds slightly sped up in the first English segment, so there may be also an element of postprocessing the dub (speeding it up/slowing it down).
I think it would be better to either slow down the underlying video or solve the overrun issue on the translation level. A good professional dubber will find translations that will even out in terms of timing. That's something an AI should be able to do better instead of worse.