Is it insulting to call a full professor Dr. Firstname Lastname in a non-academic event program? I'm in charge of putting together an event program, for a non-academic (business) event. We have several academics presenting, from mainland Europe and the UK. 

In the agenda is it appropriate to write, for example, 


Topic Title - Dr. Firstname Lastname, Professor of xyz at XYZ
University 
Topic Title - Prof. Firstname Lastname, Professor of xyz
at XYZ University 
Topic Title - Prof. Dr. Firstname Lastname, Professor of xyz at XYZ University
Topic Title - Whatever is in their linkedin profile...


(as seems to be typical on the continent)

I ask because I would like to use appropriate titles without sounding too academic and without insulting anyone. All are full professors, one emeritus. I'd like to use the same for all if possible, for consistency.  

And, I am assuming that I should use at minimum a Dr. before the name even though the job title will be listed after the name, even though speakers with MBAs etc. will not have their titles listed, and will just be Firstname Lastname... not Ms. Firstname Lastname, MBA.
For most people, insult and offense comes more from lack of care and respect than from mistakes.  I would thus recommend the following procedure:


Prepare a draft, making your best guess for each speaker based on their web presence.
Send out the draft agenda to all speakers, saying that this is the draft and you'd like corrections in case you have made mistakes in how anybody is listed.  (You probably want to run the schedule by them anyway for other purposes as well.)
Make any corrections requested by the speakers.


This way, if you get anything wrong, you're doing it in private, acknowledging possible errors, and giving them a chance to correct you in private as well.  It will be a rarely sensitive person or an unusually significant mistake that will cause offense in this way.