Thank you Kyle,
The baseline of each graph is treated like a number line. Following the table "Use and Omission of Numeric Indicator" on page 6-3 of GSTG 2022, we see that no numeric symbols are to be used on number lines so your assessment is correct.
The only part we see that will require the numeric indicator is the label for part (b) Height = 1/3.
We hope this helps!