So we were able to get a copy at MCM London of the standard issue Daggerheart book. Is there a redeem code in it for the Nexus or do we have to buy a copy there as well to be able to use all of the features?
Seems a bit off to have to pay for it twice.
This has been a point of contention for many virtual spaces for TTRPGs. I learned about this through DnDBeyond, before they were acquired by WoTC. Each of your VTTs and Digital TTRPG tools act as an independent store, more-or-less. So, in order for you to be able to access the digital content on these digital tools, you need to buy a license of sorts to access the content.
Therefore, unless Darrington Press decides to make a deal with Demiplane or another digital toolset and have a QR code or coupon code to give digital content for free, Demiplane and/or the other digital toolset provider will need to issue a fair cost to the consumer in order for them to access the content on their app/website.