If this is the Amphitheatre bed, then this is Cotinus 'Grace'. It's outside the amphitheatre area, and also outside the Europe alpine garden, so I'm not sure; photos I'm seeing of C. 'Grace' look a lot like this. It's very showy.
Using these photos only that would not be my guess. 'Grace' is half American smoke tree and shows that heritage in its branching, leaf size and inflorescence structure.
Thank you. Why would anyone develop a cultivar when the species looks as amazing as that! Never mind, I'm sure there are lots of reasons, size being one, maybe leaf colour.
I see it's featured as that in Douglas Justice's July 2020 in the Neighbourhood - UBC Botanical Garden.
