Horizontal Elderberry cuttings?

I harvested some elderberry branches, them ran out of time to process them into cuttings.
I left them upright in my stock tank pond, hopping they would keep.
By the time I hit back to them, they were mostly knocked over and many of them were totally submerged.

I processed the ones with parts above water, and planted them out.
When I went to clean up the fully submerged branches realized they had root nodules along their entire length!
Now I know they might not take, but I buried them horizontally.
The hope is they will sprout along their entire length, but if they just grow from one point that will also be great.

Googling horizontal cuttings brings up figs and hydrangeas, but nothing on elderberry or anything else.
I think rooting most of a cutting should work fine, and the horizontal burial should work as well, but I wonder if I need to leave some of it unrooted and unburied.

Any thoughts from the green mind?

Bonus!  If it's something wanted, and it's volunteering to grow, then I reckon take advantage of the situation. Any left to plant on an angle - some part of the stem above ground?   Doesn't grow, then not much lost.  Perhaps you are the first person to see this phenomenon - keep us posted.

My goats trampled some of mine horizontal and they sprouted vertical shoots so it is possible.