I would have thought the Mavic wouldn't ascend during a go-to-home this close to the homePoint. It won't if an RTH is initiated. Apparently the strategy is different if the flightAction is a OUTOF_CONTROL_GOHOME instead of an RTH.
Mavic Manual page 16:
It will ascend to 32 ft between 16 ft and 66 ft from Home Point !
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If RTH, including Smart RTH and Low Battery RTH, is triggered between 16 ft
and 66 ft (5 m and 20 m) from the home point, and Forward Vision System is
activated:
1. If aircraft's current altitude is greater than 32 ft (10 m), the aircraft will return
to the home point at the current altitude.
2. If aircraft's current altitude is lower than 32 ft (10 m), the aircraft will first
automatically ascend to 32 ft (10 m), from the current altitude.
The flight speed will be adjusted to 9 mph (14 kph). The aircraft will start
landing immediately if the Forward Vision System is deactivated. When entering
Failsafe RTH, the Forward Vision System status is evaluated and RTH will adapt
accordingly.
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