How should my co-owners find their staking verification keys?

[lastorset]

Naturally, I found this other topic immediately after posting Link a payment.addr generated with a stake.vkey to a recovery phrase

It seems to belie my assumption above:

@lastorset

I don’t find any option in Daedalus or Yoroi to export the verification staking key. (This would seem the natural thing—while it isn’t public information, the key isn’t really useful to disrupt anything except your own pool.)

Have I misunderstood, and the stake.vkey is actually sufficient to actually delegate on someone’s behalf? I had assumed the staking signing key (stake.skey) would be needed for this.