"They’re insignia?" Rotten guess – gets us eliminated (6)
I believe the answer is:
badges
'guess gets us eliminated' is the definition.
I can't tell whether this defines the answer.
'they're insignia? rotten' is the wordplay.
I cannot quite understand how this works, but
'rotten' could be 'bad' ('bad' can be similar in meaning to 'rotten') and 'bad' is found within the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for badges that I've seen before include "Emblems of membership etc." , "Emblems to signify rank or membership" , "They are worn to show membership of an organisation" , "Emblems, labels" , "Things worn to show membership or rank" .)