I'm sorry to read that the end is approaching for one of your little ones LB.
I think the gesture is beautiful, pure goodness and you are lucky to have friends that will suffer some pain in order to possibly ease your pain.
That said, Like you, this is something that I would do alone or with my wife.
and I did do this (even though I'm a husband) with my wife for sweet Ziglet a few years ago. I wept while it was happening, and after it happened for a few days, and I'm getting weepy now just thinking about it.
For me this is an immediate family thing and deeply personal.