Mismatch between variables and Figure 4/5

[pgleeson]

A/c the text:
"The equations used to derive the simulated activation are the same as in equations 3, 4 and 5, where the time constant, potential at half activation and steepness are 190 ms, 1.237 mV [14] and 6.859 mV [14], respectively."

So why is the potential at half activation here (right below) closer to 20mV?

Plot on left generated with

pynml-channelanalysis SHK_1.channel.nml -minV -60 -maxV 60