Hi,
I'm sorry to hear, you are facing trouble with it. I've done some tests with the Datasmith Exporter, but I can't reproduce any similar troubles. Are you using the File Export > Export / Export Selected or the Direct Link feature?
As you’re using the Points Cloud viewport mode please feel free to “change” the Style - Small Dot / Large Dot mode to “refresh” the viewport once the object disappears.
Thanks in advance for any further comments on this issue you can share about it with us / our user community (in case some user(s) will run into similar troubles).
Best regards,