Perhaps I’m unique here, but I’ve always thought of the corkage fee as simply compensation to the restaurant for lost alcohol sales and a discouragement towards guests simply trying to save money by bringing their own bottle.
My assumption is that in most establishments, little or none of the fee goes to the staff who actually bear the burden of opening/decanting/washing glassware. In other words, the corkage fee isn’t really a tit for tat payment for the actual opening services - it’s a fee intended to discourage people from short cutting the wine list. You’re not “buying” the glassware, you’re paying an excise tax. Almost like paying U.K. air passenger duty for your fancy wine.
In this case, I actually think OP was off base a little here by managing the glassware and not letting the sommelier do their job. Part of the fun of a vertical can be comparing multiple wines side by side. And even if it was four very different wines, multiple glasses allow slower drinkers to consume the wine at their own pace and not miss out on pours of newly opened bottles.
IME, waiving corkage fees happens often when you have a really good reason for bringing your own bottle (special occasion, dinner for the explicit purpose of opening cool bottles, etc.) - it’s just part of the hospitality of accommodating guests, especially when the rest of the meal ends up being quite profitable in its own right. (Some restaurants waive it as long as at least one purchase off the house wine list is made, for example.). It’s the restaurant’s prerogative, and once they do you should assume the rest of the service would proceed transparently as if you purchased all of the corkage bottles off their wine list.
I think the real etiquette play, as others have said, is to ensure you tip very generously for the inconvenience of the staff and to offer the sommelier the opportunity to taste the unique bottles you’re opening - neatly covering compensation for everyone slightly inconvenienced by the extra work.
Just my $0.02