Wardens are immune to lava, but attempt to avoid it even when a target is submerged in lava. This isn't in parity with Java and defeats the point of it being immune to lava.
Steps to recreate:
Make a lava pool and summon a mob/player inside of it. Make sure the mob or player is resistant to fire or immune to damage.
Spawn a warden outside of the lava.
Wait for enough vibrations to be sent out from the mob or player to cause anger.
Observe the warden fail to get to the player/mob.
Thank you for your report!
We're tracking this issue in MCPE-153582, so this ticket is being resolved and linked as a duplicate.
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