The twitch api has nothing to do with the streamers “display”. All aspects of what is shown on a stream is done locally before transmission of the data to twitch. They provide information about the stream and data points concerning yours and other peoples channels, ingest points for transmission and certain other things but not local aesthetics produced by the streamer, their broadcast software and, any add-ons created to help the stream be more “viewer friendly”.
With that said it does (twitch api) provide endpoints in which add-ons (like clr) can trigger certain effects off of that can display on the stream.
What you were asking for is something that twitch itself doesn’t provide - only third party engineers provide this; even if some of their features do trigger off endpoints twitch provided.
On a side note - I got an email with your past message and if you’re using twitch alerts you can see whether or not their service triggered the alert to display when you reicieve the json data saying it was successful(cant remember it offhand), but Tha does not mean it actually displayed on stream due to unforseen circumstances - like human error in setup of the clr or dataloss/corruption during processing (this is the internet and Tha does happen from time to time, but the guys at twitch alerts and twitch work damn hard to minimize this).
So yea you’ll know if it happened server side, not whether it actually displayed directly on the stream. Once again, to get this info, you’ll probably have to inject or create an add-on for obs or whatever streaming software you use to recognise it.
Sorry I couldn’t help more.