I think I figured it out! I started over with a child theme and was able to get the logo to appear. Under the “Appearance” “Customize” area, where it says, “Site Identity,” make sure the “Show Header Text” box is checked. When I unchecked it, the logo disappeared along with the text. When the box is checked, the logo reappears!!
DON’T CONFUSE the “Show Header Text” radio button with the “Display Header Text” check box that is underneath the Copyright text box. I have my “Show Header Text” radio button set to “no” and my “Display Header Text” box checked to indicate “yes.”