After much testing, I'm quite sure that it is the "Elemental Potency" perk in the Conjuration tree which is breaking the ability for the Sanguine Rose to spawn the summon.

I loaded some old saves and was able to get the Rose to summon properly.

Found a save before I had Elemental Potency but a few perks and tried to use the Rose. Works fine. Selected "Elemental Potency" and it went right back to making the summon sound but no actual summon.

I would guess having the perk makes the Rose try and find a "Potent" version of the summon when none exists.

Give it a try for yourself or better yet - someone fix it!

I'm about to select this talent in the near future. I hope it gets fixed, because I prefer my summons over the staff summons. However, I don't want my staff to stop working. I used my wabbajack eventually. I plan to use my sanguine rose someday when I need it as well.