CCP Nullarbor confirmed that citadel markets will not appear in CREST:
https://forums.eveonline.com/default.aspx?g=posts&m=6333512#post6333512
And a minor pedantic point: "EMDR scraping" wasn't a thing. "Cache scraping" is the term you meant.
As far as I know, there's nothing to stop people from continuing to scrape the cache and sending data to EMDR*, but I don't know if the citadel market data appears in the same place as regular markets; and there's still the very good point Nullarbor makes about the citadel markets depending on the observer. I've had this discussion recently in another game; does it make sense, and is it useful, to be broadcasting non-publicly-available orders over EMDR? The answer, I suspect, will depend on your use-case for the data.
* Though CCP have regularly expressed a desire to change the way the cache works so that this will no longer be possible, I don't think it's been done yet