Graham may have threatened Olfie that he had killed the yeti and crystal dragon, angering Olfie who had recently been with them.
The Hobblepots remember seeing an eldest bear or a bearist elder while honeymooning in the Great Mountains (KQGS). Perhaps both were wrong and they actually saw Bill or another yeti.
Rosella and Graham reminisice about an adventure where they helped a yeti on a blind date (this maybe a reference to Bill).
Many years later, Graham would actually get around to injuring or killing (or tricking or befriending?) Bill it seems later in his life
Behind the scenesEdit
It would seem that in the reimagined universe, Yeti are more sentient that is believed in the original series universe.