I'll make some comments.
First, there are no real pro-china leaders in VCP. They have been purged long ago since the 70s. Even "pro-China" people like Nguyen Phu Trong are only, in Hilary Clinton's word to describe Australia in similar situation, DOUBLE-CROSSING. These "pro-China" leaders are not 100% sincere in having good relationship with China but only want to get as much benefits from both China AND US.
Both China and US are not stupid, they know when their "friend" double-cross them, or what I called earlier play the two-face game. Clinton openly rebuked Australia for doing it and China also did the same recently. But Viet members twist the story and spread lies that Vietnam was acting a good friend to China, why China act so harsh blah blah.
The truth is that China has finally spoken up about VN double-crossing game and their leaders got shocked. China said you either with us or you are against us. This is funny because the US also has the same attitude, either you're with us or you are against us, you want weapons and support from us? change your politics. So VN is check-mated. They taught they clever by double-crossing with the US and China but they lose at the end.
Now the legitimacy of the VCP, or any government, lies in their ability to develope the country and security. We've seen plenty of news that their economic reform is a FAILURE with underforming growth rates, huge public debt, bad data, etc. Simply, they've failed their target by a big margin. The only area left to prove themselves is the security of their country. But as the recent SCS dispute shows, they got exposed as impotent. On the one hand, they want to instigate the anti-China sentiment in the Viet civilians and promote the China-threat propaganda because this is their only place left to prove their legitimacy (and distraction from poor economy). But on the other hand, they got exposed as being weak and impotent against the China. The US tempted them to come on their side but the US won't fully support them until they change their politics, as usual. So now, its like they got check-mated. All those time playing the two-face game, and promoting anti-china sentiment, returned to kick them in the @ss.
The pro-US leaders don't have much to fear, because most of their friends and family are probably in powerful position in various state companies and industries. So if there is a revolution and a change of politics, they will do fine, because even the US can't just restructure those industry overnight. So these people, like Tan Dung, don't care about revolution and maybe welcome it. I also think that the military will also be safe because they have experiences and leadership and the US seem to have good relationship with them.
The leaders that are "pro-China", like Phu Trong, will lose the most because they probably have no more place after the revolution. They will lose their position and influences. So surely they don't want a revolution or change of politics. So this is why I think there is an internal conflict.