Did Ollivander know about the Horcruxes

[justcarol67]

No: HPFGUIDX 138609

I just had an idea that may or may not be important--it came to me in
a flash so it felt like an inspiration, anyway!

Ollivander says in SS/PS, in a scene which I think foreshadows a lot
of future events, "He who must not be named did great things.
Terrible, but great." He can't mean all the murder and mayhem LV has
caused, which qualifies as terrible but not great. Can he possibly
know about the Horcruxes, which appear to be very complicated (and
certainly terrible) magic, going beyond what anyone else has done and
consequently qualifying (from Ollivander's somewhat amoral
perspective) as "great"? 

Any thoughts about how much Ollivander might know and how it ties in
with his disappearance?

Carol, using up her last post for the night and hoping someone will
answer!