Legal Question in Civil Litigation in California

It is hard to tell, without reviewing the docket sheet for the case. I cannot tell what type of hearing it was, where the plaintiff failed to appear.

If the motion is in fact on file, the plaintiff must oppose it. I cannot tell you if the entry of default will play a role here, since I cannot see the docket.

You need to talk to an experienced litigator here. The failure to show at a hearing may prove to be very costly to your case.

Something is missing. If you served the defendant, he did not respond, and then had his default entered, he should not have been able to file an Anti-SLAPP motion. I suspect that the default was never actually entered. An Anti-SLAPP motion is a valid response to some lawsuits. If they served the motion on you and you did not respond, your options may be limited. You need to consult with an attorney that has litigation and Anti-SLAPP experience.