Currently, logo is not displayed on reports displayed as PDF. Is because iDempiere tries to display iDempiere.png or iDempiereHR.png ; but those files are missing, and I think they were replaced by header-logo.png.
Attached patch keeps old methods (that may be used in plugins) and add a new one, dedicated to header-logo.png
https://groups.google.com/g/idempiere/c/WW9gsolk6vA