Don't change the slant... They're already drawn slanted, you don't need to specify any additional values.
How do they show up on the e-reader? "Calendas-Bold" or "Calendas Bold"?
Because if it shows up as "Calendas Bold", then the e-reader probably uses the "Name For Humans" field (which I think corresponds to "Menu Name" from TypeTool) to group them, instead of by Family Name like in basically any other computer software. Does this make any sense? Try changing the "Name For Humans" field to just "Calendas" for all 3 files.