SSTableWriter.Builder.build() takes tables that resulted from streaming, repair, bootstrapping, et cetera and builds the indexes and bloom filters before "adding" it so the current node is aware of it.
However, if there is data present in the cache for a row that is also present in the streamed table the row cache can over shadow the data in the newly built table. In other words, until the row in row cache is removed from the cache (e.g. because it's pushed out because of size, the node is restarted, the cache is manually cleared) the data in the newly built table will never be returned to clients.
The solution that seems most reasonable at this point is to have SSTableWriter.Builder.build() (or something below it) update the row cache if the row key in the table being built is also present in the cache.