Boss/Lockbox didn't drop the key for me. Tried with 2nd agent - forgot the lockbox at first, killed boss - no key. Went back and got the key from the lockbox.
Tried it with 1st agent - and it worked again. So maybe it helps to kill the boss first and only then raid the lockbox?
Hi @Major_Failure1 ! Thank you so much for providing your workaround. I've shared it with the team investigating this issue. 
@tadidesign Hello! I am sorry to hear that you did not receive the key. Were you able to check the lockbox after killing the boss to see if the key is there? Thanks for the tip, @Noxious81!
Thank you for all of these details @tadidesign! To clarify based on these previous messages, were you able to resolve this and unlock the SHD room with the key?
@tadidesign I'm so glad to hear all of that! Thank you so much for the confirmation. Good news all around! 
@t0rv4lds Were you able to collect the key from the white box on the wall rather than the flame thrower enemy as mentioned in this thread? This appears to have worked for other players.
@robds71 Hello there!
Sorry to hear you're still encountering issues with the sewer SHD cache.
Would you be able to let us know if you were able to loot this key from the white box on the wall, rather than the flame thrower NPC?
Thank you.
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