Finally. I wasn't playing with this one. Missed the Newegg combo drops on Thursday, so made sure I was ready on Friday. Did a test run order with the Newegg app using Apple Pay 15 minutes before the drop was expected. Made sure my session was active and didn't require re-authentication or sign-in.
Filtered my search in the Newegg app just to the combos I wanted ("3060 ti msi combo") so they were the only results, then waited. Refreshed on both the site on my computer, as well as on my phone, about every 30 seconds in order to not be IP banned.
3 minutes or so after 4PST. Refreshed, and selected the cheapest "MSI 3060 Ti Combo" which showed in stock. Pressed Apple Pay. Checked out, all within the span of 10 seconds. An 'Apple Pay was charged' email was sent to me immediately.
Checked my order history to discover, despite selecting a combo, the transaction was actually for a single card. Lucky.
In summary: I got the card I intended to get, but despite expecting to pay more for a combo and likely return the add-on item, it actually checked-out for a single card. Win-win.
Also, Apple Pay is a killer-app in the COVID-Era consumer, limited supply, arms race. It's literally the fastest way to pay.