This problem is no longer relevant in Search 6:

1. @IndexedEmbedded.prefix is deprecated and @IndexedEmbedded.name should be used instead.
2. @IndexedEmbedded.prefix is ignored when set to an empty string (the empty string is the default)
3. Having multiple {{@IndexedEmbedded}}s with the same prefix and fields with the same name with result in duplicate fields, which will be detected at bootstrap and lead to a boot failure.