Looking for it on my controller too.
@Spirit
Wait... wait... i will try and get it on a new character... will get back to you asap
Got it yesterday thanks to someone whose name was too long for me to remember 
Third accolade, yay !
Still looking for spelunker for my blaster for the longest time. Anyone have it?
What story arc serves it up?
you can only get the mission for it between 10th to 14th level from the following contacts: Dr. Trevor Seaborn, Hugo Redding and Haley Philips. The mission you actually get the badge in is the Rescue Fortune Teller one.
Defiant 50: Blonde Justice inv/ss; Lady Aminta emp/elec; Sierra Colt merc/traps; Tess LaCoyle elec/elec (blaster); Powerstorm elec/elec (brute);
Union 50: @Steel Dancer WP/DB; Blast Pulse Fire/Rad (corr); Bitter Twilight Earth/Psi (dom); Compassionate Emp/Psi;
Freedom 50: Incandescent Blaze ElecAm/Fire;
If anyone has the Spelunker badge mish, I'm looking for it on my Troller in order to get the Atlas Medallion.
If you have the mish and don't mind me tagging along, please let me know @Aerys