I know nothing of this Burgundy cv, but the species is known for its vigorous root system, healthy older specimens commonly developing buttressed roots. It is always advised to plant these a fair distance from underground pipes and other amenities.

They're not known as a particularly fast grower, so perhaps the rapid rate of growth in your own plant gives a clue as to why it toppled...whether it's the nature of your particular variety or the excessive water, too much top growth at the expense of good root and trunk development is a recipe for disaster in practically any plant.

I've never seen one staked.