LT3741-1 Bottom Gate Never Turns On

I have fabricated and assembled a PCB that contains eight LT3741-1 regulators in parallel in order to do high current testing on PCB traces. I am at an early stage where I just have one of the regulators populated with components. When enabling the regulator only top gate fires off. I have tried various resistive loads and the activity remains the same. Absolutely no activity on bottom gate is detected.

Power integrity appears fine on VCC_INT. Vref comes up just fine. VC goes to 3.0V and sees sawtooth shaped drops. Pulse width on top gate is around 100ns and the frequency is oddly around 85kHz.

LTSpice shows a nice sloping rise on Bottom Gate upon asserting Enable. This is not observed in hardware. Any help is much appreciated.

Target max output current will be up to 50A per regulator but for now I am just trying to get a single regulator to run at any current.

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