Chain slipping on brand new bike, bike shop is stumped
The problem turned out to be the crank assembly. Apparently the chain ring offset on the original crank was wrong. The replacement that Shimano sent (having been given the bike year/make/model/groupset info etc) was a totally different offset than the one Kona shipped with the bike. The new crank resolved the chain slipping problem.
I don't know who messed up here. The bike shop thinks Kona shipped the bike with the wrong hardware, possibly on just my bike or potentially some set of the 2020 Lava Domes. Kona certainly didn't take responsibility originally though. Regardless, the issue was resolved by putting the right parts on the bike, thanks to Shimano. Thank you everyone for your responses and suggestions.