I don't know if you would call my kid's larger hemangioma a lower lid one or not. I refer to it as the cheek area, but I could email some photos - at one point it was certainly obstructing a portion of her field of vision.
She has had two plastic surgeries. I think that you are fortunate that you found someone to treat your son so early on. I don't know what his case looks like, but it would be unusual for anyone to recommend surgery for a 6 week old, unless there was imminent danger of vision loss.
Let me know if you want to see before/after photos - I can email.