Thank you! I have unbound DNS set, I have some Blocklist (Steven Black list), DNS pointed to my OPNsense router. Not sure if this setup blocks grapheneos.org but I whitelisted it and now it works. I wasn't able to install any app from the app store, not only Accrescent, while playing with the settings of OPNsense, it still didn't work, so I tried to install other apps, with the same result, restarted both, phone and OPNsense, then I realized that GOS didn't connect to wifi automatically, which is strange, after turning on wifi I was able to install Accrescent. So thanks, now all OK :)
Regarding any local dns blocking (e.g. pihole or adguard home) - no, just this Steven Blacklist, funny is that I haven't seen GOS in the list of blocked domains. But the list was extremely long and it might be that due to no wifi on Pixel....