In the most recent snapshot where the new deepslate ores were added I found that regular lapis ore was spawning in place of deepslate lapis ore. I created a fresh world and have seen the other deepslate ores but despite looking both in spectator mode and checking with fill commands at the point where lapis spawns in deepslate it has always been regular lapis as low as -16 surrounded by deepslate. I'd assume either lapis ore spawning wasn't changed in the code or was set as lapis ore instead of deepslate lapis ore.