I have been observing this for a long time. Whenever the properly fermented and dried cocoa beans were exposed to moist environment, the shells quickly absorb moist and the white to grey molds begin growing. Usually affects only the shell but it removes the nice vinegary aroma.
I was worried. Those might have the capability of producing aflatoxin, a potent poison. Identification was hard since the keyword “cocoa mold” was yielding the literal “mould” for chocolate making. The other keyword “cocoa fungi” was focused on cocoa plant and pod diseases.
A study by Marina Copetti et. al. (Aflatoxenic fungi and aflatoxin in cocoa) found out a number of aflatoxin producing strains in cocoa but the amount they can produce are minimal.
I guess should worry less about its identification and focus more on quality management.