There's an ongoing debate about this.
Snowflake moray eels belong in the genus Echidna, the pebble-tooth morays. These morays eat crustaceans, as opposed to the eels of the genus Gymnothorax and others, which eat primarily fish. Therefore, snowflakes generally won't eat fish, but there are some specimens that are exceptions to the rule. Also, sick or dying fish are much more likely to be eaten.
So, probably yes, but there is some risk involved.