I recently committed a big error by leaving my loco in its plastic case on a table in the afternoon So. Cal. sun.  The result was a melt down of the tender shell and the cab on the loco shell .  After removing the tender shell, I found no physical evidence of damage to the PC board or the components.  However, when I put it on my programming track, I could not access the loco with my Digitrax Zephyr system.  When I tried to read the loco address the response wwas dnd, no decoder detected.
I checked the Bachmann online Parts catalog for the 4-8-2 Heavy Mountan and found that the PC Board with decoder was not in stock.  I called the Bachmann Service Dept. and they verified that this part was not available and did not know if it would come back in stock.  Also, no Spectrum Heavy Mountains were available if the loco was returned for service.  I did order a replacement loco and tender shell to repair the cosmetic damage done by the afternoon sun tan.
With the tender shell removed, it appears that the DCC decoder is hard wired to the PC board.  Can this decoder be removed and a new one wired using the existing wires?  If so, has anyone done this and what decoder?
Thanks for any assistance you can provide.  This loco was the pride of my fleet 
George