Identification: Cornus controversa 'Variegata'?

Although I found a statement that Cornus alternifolia is the only dogwood with alternate branching, Cornus controversa is another closely related dogwood that has alternate branching. I would love to know how to distinguish them. Is it that leaf pedicels on C. alternifolia are red?

I assumed that this tree at Butchart Gardens was C. alternifolia; it seemed to be just what I would call "pagoda dogwood", but I see a statement in a Vancouver Sun article from 2011 (Beautiful Butchart Gardens) about Butchart's "special specimen tree, an elegant Cornus controversa variegata". But that tree was supposed to be in the Japanese garden, and my photo was taken outside the rose garden. I'm guessing it also is Cornus controversa 'Variegata'. Can anyone tell from the photos? Or does anyone know from knowledge of Butchart Gardens?

 

Whatever it is, those are gorgeous photos!

 

As with the parent species the cultivars can be told apart by leaf size.

 

OK, thanks. So, leaf size:
Cornus controversa, from Cornus controversa in Flora of China @ efloras.org:

Leaf blade broadly ovate or broadly elliptic-ovate, 5–13 × 3–9 cm, abaxially light or grayish green, sparsely pubescent with appressed trichomes, papillate, veins 6 or 7(–9), abaxially raised and slightly purplish, base subrounded, apex acute or acuminate.​

And also:

Bark dark gray or yellowish gray, smooth​

Cornus alternifolia, from Cornus alternifolia in Flora of North America @ efloras.org

Leaves: petiole 20–50 mm; blade narrowly to broadly ovate or obovate, 4–12 × 2.3–7 cm, base usually cuneate, rarely rounded, apex abruptly acuminate or cuspidate, abaxial surface yellow-green, papillose, appressed-hairy, adaxial surface dark green, glabrate; secondary veins 5–6 per side, most arising from basal 1/2.
[ B]ark thick, corky, plates​

So C. alternifolia leaves are a little smaller (I'm not really so good at 1 cm differences, maybe one fewer secondary vein), bark not smooth. And it can be shrubbier.

There is also Cornus macrophylla to distinguish. Well, opposite leaves should be the clincher. And true to the name, leaves something like twice as large. From Cornus macrophylla in Flora of China @ efloras.org:

Leaves opposite; petiole 1.5–3 cm; leaf blade light green to slightly white abaxially, broadly elliptic, broadly ovate, or ovate-oblong, rarely elliptic, 9–16(–18) × 3.5–8.8 cm, papery,
Bark grayish brown or grayish black, smooth when young, scaly when old​

BPotD: Cornus macrophylla

 

When viewed in person there is a clearly apparent difference in coarseness of branching and of leaf size between 'Argentea' and the controversa cultivars. Even when 'Argentea' is 19 ft. tall, as one in Seattle was at one point.