Key worker said to sneak out instead of say goodbye

[NameChange2306]

The nursery we’ve chosen for our 10 month old is really accommodating, adding personal touches on the settling in sessions for our DS and very homely as it’s a small setting of only 20 children.
DS has been quite unsettled at the nursery trial days so far, we stayed with him the entire first one. When it came to the second we were going to leave him for 15 mins to start with as the sessions are an hour long. His key worker told us both not to stay goodbye and just sneak out so he doesn’t get upset.
Is this correct? I’m finding myself conflicted in this, we usually sneak out when he’s playing happily with toys or distracted. Which seems better than gaining his attention back to say goodbye then leaving him sobbing again.
On the other hand I keep reading that saying goodbye is important.

I work with children 24 months+ but I would never advise a sneak out. I always say to the parents, a kiss and a cuddle, say goodbye, then leave. I can't imagine the terror a small child must feel to know their parent is there, be happily playing, then turn around and find them gone. Forever? Who knows!

A gentle and firm goodbye, and then a return with joy, lets them know that although their parents may leave, they always come back. Please don't just disappear. Goodbye, see you soon.