Did Mary Lincoln need committal?

[Eva Elisabeth]

And, he relied on a lot of people and doctors in making the decision.

It was his (active) decision to bring her to trial. Most of the people whom he relied on hadn't seen Mary for a long time or (three of the doctors) had never seen her. They made their decision upon what he told them. Would he have wanted to rely in any other decision?
Well, he might have had his noble Victorian motives, still it's difficult for me to understand. And I'm still not sure in how far money played a role in his decision.

When Robert was ambassador to the UK, most likely he met Queen Victoria? Are there any accounts in this regard?