I don't mean to be trite ... but is not that 5 kinds of people?
It's a good question to analyse, or pose alternatives for.
To the first category, I'd add propose a split ... between those for whom BKism is just a brand of Hinduism Lite™ - most of whom are Indians, and many Indians abroad - and those for who BKism fulfils some kind of social or personal need not being met elsewhere, eg a substitute family where there were conflicts before.
The first doesn't really 'get' BKism at all ... they just see a "holy person" and respond. The second might get BKism is a bit weird/odd/dubious at some higher ijtellectual level but be over ruled by their lower emotional needs (included in them, I'd add Dadi worshippers).
Your categorisation of those who have donated all of their property and cannot leave because of financial reasons is a good one and, I think, stands alone. These are individuals who have seen through BKism, for whom the charade has crumbled, but are just stuck with nowhere else to go, no way to get back their investment, and too weak or weakened to remake another life. Some have tried to get their properties back and failed ... the BKs come up with a 'gotcha' line about how you can get back a donation from a charity (presumably because they have already claimed tax relief for it and do not want to repay it too).
The young girls who leave their families - who are forced to pay during their training and surrender their dowries - and are moved away by the BKs are another tragedy. What will come of them? Few to no one would want to marry them, apart from running a cult what skills or training do they receive? Many are beyond child bearing age. Yes, amongst them might be those lacking courage but also those just plain and simply wanting to get back for what they gave when they were young.
Now the last category, your second, is much more clear ... those who knows the truth behind BK but still continue to be in BK because they are part of leadership who get advantages of cult. It's a very small percentage indeed. I'd say probably less than 100 people ... a few tens even.
Then I think there is a second division of middle management who look up and aspire to become one of them but are still caught up in the brainwash and just too busy to stop and think. They can afford to question as their entire world would fall to pieces if they did.
A classical view of cult followers in the West, from sociologists, is that individuals join cults and adopt a ready-made 'cult persona' to act as a mask ... whilst they heal/work on/avoid other personal problem they might have.
I am not so sure that theory applies to Indians and the BKWSU.
My question ... do Indians join the BKWSU to make them feel superior, eg to escape or rise up the caste system?
Do they really believe they are superior "Brahmins", superior to impure Shudra Hindus, and is that a motivation for them?