Re: speaking of "situations"
I sympathize with you, and more with him.
He needs better skills, which he does not have. Maybe you can practice situations with him so that he can learn these skills. Looking you in the eye while speaking to you is a good start. Then you can practice other social/learning situations until he is comfortable with them. I know you would not throw your child in a pond when he could not swim, but it is almost like that. You have to teach him to swim first. Give him the skills he needs to deal with other people before you throw him out there hoping he will learn to swim out of sheer necessity. These skills may not be learned this year or next, but obviously he is taking his stress into his body and it is quite hard on him. Some children are not ready for school until they are seven.
Besides school, is he into other social situations like church activities, sports, or Boy Scouts, or anywhere he can help get those skills?
Please don't be offended at what I am saying, because you sound like a really great mother. And he sounds really darling.
I have never used lobelia as anything other than a tincture. I tried powder, making it into a tea, and it really wasn't that effective. So I understand why you do not want to use the capsules. I have made lobelia tincture from the fresh cut herb, but that is a different story, too. I agree with you on not using it, in this case.