As long as he didn't *do anything* when she said "no", it's not a problem. It is not illegal to ask to fuck your mom, and then not do it when she says "no". If everyone (including Barb) testifies that he did not do anything on the occasions where she said "no", the prosecution has nothing. For it to be rape, they would have to prove that he did indeed fuck her when she said "no". This is why a rape charge is exponentially harder to prove without Barb's consent. For the incest charge, they just have to prove that he fucked her at any point, regardless of her agreement at the time.
Heilberg probably ordered those to support a claim of diminished capacity. This is different from insanity. With diminished capacity, you are still guilty of the crime, but your punishment should be less considering the totality of the circumstances. This includes the decision whether to charge the incest as a misdemeanor or a felony. i.e. it does not change the fact that a crime occurred, but it can change the nature of the crime and the nature of the punishment.
The end goal of a diminished capacity argument is a lesser charge, or failing that, lesser punishment for the charge.
From what I've been able to discover, Virginia has mostly done away with halfway houses for non-juveniles. Being placed on the SOR would be incredibly bad for Chris. Virginia is one of the states where prospects for a high-tier sex offender are very grim, and basically guarantee that they will return to prison.
That said I consider it INCREDIBLY unlikely that Chris will be placed on the SOR at any tier higher than 1. Heilberg simply will not accept a rape charge in any plea agreement. The worst case plea agreement would be felony incest with a tier 1 SOR listing. I still consider that unlikely, and any agreement will be misdemeanor incest, or felony incest with no SOR listing.
That said, even at Tier 1, there would be a gajillion ways for Chris to fuck up just wandering around too close to a playground because he wanted to play on the swings.
There are actually many supportive tard housing facilities in Virginia where he could be housed compassionately, the only question is how they would be paid for.