Which Boron? If it’s a 2G/3G it will need 2A by itself so there won’t be 500 mA left over for the Argon and you’d need a 2.5A power supply.
Other than that, presumably there’s a loss of voltage. That cable does not seem particularly long. If it’s a standard 26 AWG cable that should be fine, but if you have a thin or flat cable, that could be as small as 32 AWG, which is probably too small.
Ideally, if you have an oscilloscope you could see what the power is doing. Adding a large capacitor at the Argon VUSB may help.