Sexing juvenile ackie monitor

[elarinyas_musings]

I have a 4 1/2 month old red ackie and have been trying the HMI technique described in the Danny Brown paper to sex the individual. The paper states that juvenile monitors with a SVL of >5 cm can be sexed using this method. I have tried it several times, but I am not confident in what I am seeing. Perhaps it is the light I am using or my unfamiliarity with what I am looking for. Can someone with more experience offer their input? I’ve attached pictures for reference below. Also, when feeling the spurs they do catch a bit on my fingers so I have been leaning male.