Found the Geni "Help", way way down in small print at the bottom of the page. Here is what they say on the matter:
" How can I display an adoption on my Tree?
We currently do not have a way to represent this on the site. Therefore, you may choose to work on separate Trees until the option becomes available. Otherwise, you may choose to create a secondary node on the same Tree to include the other set of parents"
Can't say I find this very helpful, but I guess I will just leave Al as a "merge issue" for now. I actually find that funny since what else is adoption but a merge issue, really? lol