Adding some data points for BJs:
I used RNM at 5% and received the activation email before my order but did not get any confirmation that this order went through. No Email and it's not showing up in my RMN dashboard.
I purchased 11 X $100 and 1 X $50 DGC from BJs on 11/15/22.
I didn't have any additional CC offers to use.
On 11/16/22 I got a shipment confirmation for the 11 X $100 DGC.
On 11/17/22 I got a shipment confirmation for the 1 X $50 DGC.
On 11/19/22 I received the $50 DGC in a padded envelope in my normal mailbox and it activated just fine.
On 11/25/22 I received the 11X $100 DGC a UPS "express" box on my porch.
All of these activated just fine also.
One thing I noted is that I received a shrink wrapped pre-pack of 10 DGC that were all on a single activation sheet and the single $100 came on a separate activation sheet.
I am guessing that only having to scan the code on a single pack that activated all 10 DGC is much simpler and carries less risk of human error.
Something to keep in mind if you plan to buy a lot from BJs. I've had issues in the past where some of my BJs cards weren't properly activated. Buying them in the 10 pack could prevent that.