Zen30 and bathroom fan/light and vanity light

I have a 2 gang box with 2 dumb switches. One controls the heat of a bathroom fan, the other switch controls a vanity light, plus the light and exhaust fan for the bathroom fan unit. It's all on one 20amp circuit (required for the bathroom fan unit). I will leave the dumb switch alone that controls the heat within the fan unit. Unfortunately, there is only 1 load wire coming to the switch to control the vanity light & bathroom fan/light. I would have to cut into the walls and rewire which I am not comfortable doing.

I would like to add a smart switch that could handle the amp from the vanity light and bathroom fan light/fan, but separate the control to the vanity light. I spoke with Zooz and they did not recommend using a Zen51 or a Zen71 as it would not be able to handle the impulse load from the exhaust fan, but they noted the Zen30 would likely be able to handle it. Still waiting on Zooz to respond, but does it sound reasonable, or has anyone else had success in this scenario? I was thinking of using the Zen30, but connect the load for the vanity light & bathroom fan/light to the relay button on the zen30, but cap the dimmer load, would follow the rest of the ZNE30 wiring instructions. Then replace the vanity light with a smart bulb and set a rule to ignore physical switch of the relay button and program the dimmer button all via Hubitat.

I'm probably missing something, but in that plan, how do you plan to control the exhaust fan/light if the relay button is set to ignore physical input (or is in smart-bulb mode)?

I'm using zen71s in 2 different bathrooms to control the exhaust fans for a couple years now, I use the built-in off-timer in the switch to have a set run-time and they never get left on.

You should be able to do what I think you're describing with the Zen30, run the higher amp load through the relay with direct physical control and then use the dimmer on the zen30 (with no load connected) to control a smart bulb for the light. I use a zen72 with no load in my living room as a remote for a shelly dimmer connected directly to load for a wiring situation I also did not want to open up walls for.

good point. guess I could control both as on/off on the relay button but use the dimmer button without the load to dim a smart bulb. Will keep thinking of other options.