Hi there! I just recently trained a “new” barista who had previously worked inside a grocery store kiosk as well. Since it’s a new company, your friend will need to be rehired.

When I originally came to Starbucks corporate, I had hoped the same thing as I was previously a manager (or at least, the most senior employee doing manager responsibilities) at a Barnes & Nobel Café. I had hoped to be hired on as a SSV, but multiple managers in my area told me they only promote to the position from within. However, I’ve been promoted to SSV within 7 months of being there :)

Well.... I know they've hired ASM's from the outside, with absolutely NO Starbucks experience, specifically to train them to take over a store. Now it's possible a kiosk store still may not have all of the experience to be fully ready to be a shift. And the pay scale could be less than they expect.
But. Having said that there's no reason they shouldn't put applications in, in pursuit of being a shift. After all they do the interviews to get a better feel for the applicants.

I’m the only shift at my store that has worked my way up from barista, the rest are outside hires. It’s definitely possible for your friend to be hired in as a shift! I would tell him to go for it, it definitely doesnt hurt to try.

They’re going through a different process of hiring shifts now, it’s more of an interview position but you definitely need to retrain because kiosk locations are not by company standards.

Either way he’s going to need to be retrained. I would suggest applying as a barista then be a shift