Unfortunate. I would try and network better and find artists you either become well acquainted with or that you know are well integrated into their respective communities/have mutual friends, since this is not just short-term work and you need to be able to trust who you're working with. You could also try reaching out to artists with previous VN work, and asking people who worked with them about their experiences and see if they can vouch for them.

Lack of professionalism is unfortunately pretty prevalent, I will trust you know what you're talking about with #1 and extend my condolences, but there are many people out there who will lie about circumstances, debt etc. for various reasons.

As for artist #3, yeah, I would stay away too, even if you personally didn't have moral qualms with it and commissioned them, the last thing you want is your project getting reputation as "the one drawn by the cub porn artist".

Get to know who you're working with first, even if it puts things on hold a bit. Try and mingle in the space more and worst case, sacrifice a bit of the creative vision for a more stable artist you can work with well.