ethics - First-year PhD giving a talk among well-established researchers in the field

I am currently a first-year Ph.D. student, before that (as I have posted about before) I was forced to leave my Ph.D. program after one year because of a bullying supervisor. Previously, I made a good relationship with other researchers in my field and other scientific volunteering activities.

Now, there is a workshop at a highly ranked conference, and I asked about the possibility of sending a paper for the workshop. They don't solicit papers, however, I have a good relationship with the professor who is the main organizer of the workshop, and they voluntarily asked me to be a speaker in the workshop for 30 minutes.

The other speakers are the most well-established researchers in my field, I felt excited but afraid in the same time. I don't have yet any publications concerning the current research. I don't know if I should apologize, maybe the professor does not know that I have been kicked out from the earlier program. I don't know what I should do, all the speakers are the elite and I think I am not deserving to be among them as I don't have the same experience.

Should I try or would this be counterproductive to my future career?

EDIT 1

Thanks for answers encouraging me to try, while there are pragmatic answers that I don't have to waste the audience time, honestly, I have self low esteem since all peers have papers published in top journals and conferences, I don't know why the organizers listed me as a speaker, I am not doing great as other students or there is no indication in the right moment that I am doing fantastic research.

Answer

Let's flip this question around and imagine that you, as a first year anthropology PhD student, are now visiting your high school. One of the students asked your former teachers if you would be interested in a local, anthropology-related research project they were doing (e.g., they could be investigating the attitudes of people towards those who are HIV positive, and contrasting how that varies between countries). The teacher promptly arranged for them to give a talk on their results while you were there.

The student feels excited but afraid at having to give this talk. She knows she doesn't have the pedigree you have, she doesn't know if she should apologize, maybe you don't know she flunked her latest exam, and she thinks she is not deserving to be giving the talk because she doesn't have as much experience as you. Should she go ahead and give the talk or would it be counterproductive to her future career?

I'm pretty confident you will say she should go ahead, and the same applies to you. These well-established researchers probably know (or can tell) you're a PhD student, and will not demand that you have done groundbreaking work on par with theirs. Instead of focusing on all the things that could go wrong, think of all the things that could go right: you get to present your work to a well-established audience. They're the people you most want to know your results. You get to network with them. You get to practice skills that you'll undoubtedly need later in your career. What's the worst that can happen anyway? Even if you give a truly atrocious talk they'll probably all have forgotten about it by next year.

tl; dr: stop worrying and do it.