New, stricter criteria:

Any of the 7 people listed here or in earlier versions as the original 7 researchers excluding Hyun-tak Kim. https://en.wikipedia.org/wiki/LK-99 will speak at a conference as described below, excluding ones run by APL (which is some sort of "easy-to-get-into" conference/journal thing which apparently does low/no quality filtering)

The must be about physics. It cannot be an apology or examination of past failures; they must be presenting their own new research (new to the world, including lk-99) positively, and have been selected due to the merit of the research, not as an example of failure or other similar fallout from LK-99's failure. Obviously, if LK-99 turns out to be true, then speaking out about it will be frequent and common, and this will YES easily. It can't be just a poster they have to speak.

The conference must be attended by at least 100 researchers in the field of physics, and must be about physics. It should be a "mainstream" conference. Hard to define, but basically, one which say at least 20% of active physics professors do not dismiss as pseudoscience. "International" means at least some speakers must be affiliated with overseas universities or research labs, etc. bit including the LK99 guys.

There has to be evidence such as photos of the speech, a video or a recording. Or written support from multiple, real, independent, currently employed "legitimate" physicists.

Judgement will be about whether any of them has actually been approved by a real physics group to speak.

EDIT 2/23 The conference must be "selective", that is, it must not be one where you 1) have the credential 2) join some org 3) meet a low bar.

It should be more like one where there is a review process which does not accept all or even most of the potential speakers; instead, it looks for the best people to speak.