Windward Hawaii waters get VERY choppy, with serious ground swells and wind swells, cliffside reflective waves, heavy trade winds, currents. People get violently ill (and gray) from seasickness even on completely fair and normal days
The only windward operator I've dived with in Hawaii runs a constant flagged buoy (not an SMB) on the surface for the whole dive, from the start of the dive, on every dive. The guide tows it along with the group and the boat follows it.
"Watching for bubbles?"
You won't even see a 6ft SMB out there unless it's ≤200 ft away, fully inflated, and held completely upright. You won't hear anything over the wind and waves.
You might see a signal mirror, but the sight lines are hopeless from a small craft as soon as the chop/swell is over ~3-5ft.
The Nautilus VHF/AIS beacons do work when properly programmed, and can show surfaced divers on the chartplotter in 'test' mode for a vessel that has AIS & MMSI