If I may add my observations: both the PDF from you and from @maxim_k drop the same roof lines when printed to our two printers here. Weird.

But... if I use the MONOCHROME.CTB to plot your file to PDF, then print it to our two printers (HP and Sharp), the lines that disappeared from your two PDFs print just fine now. See attached test PDFs I tried here.

Can you, as a test, use the MONOCHROME.CTB file and confirm if the problem of missing lines for your recipients still exists?