I know. I wish this site was as easy as in the past to update. Unfortunately, Yasl does all the stuff now, and i hope it isn't a burden.
You should be able to temporarily change the main logo by using the File Manager in cPanel, or by FTP. Rename the file "public_html/Themes/green-ornamental_09/images/psf.png" and upload the new one where it was before. When done, delete or rename the new one and move the old one back.
Or just chuck the temporary logo at me over PM