Aircraft descents too steep, landing outside of airport

[sfo]

Consider the following scenario running with the current master 849d76f:

0:00:00.00>PAN EHAM
0:00:00.00>CRE ACIFL A320 EH625 182 5000 250
0:00:00.00>ACIFL ADDWPT EH630
0:00:00.00>ACIFL ADDWPT EHAM/RW18C
0:00:00.00>ACIFL DEST EHAM
0:00:00.00>ACIFL LNAV ON
0:00:00.00>ACIFL VNAV ON

The aircraft starts descending immediately on start of scenario. At EH630 (FAF, G/S intercept altitude is 2,000 ft), the aircraft reaches ~ 3,000 ft. So it's 1,000 ft above the G/S. This would require a 4.55° slope.
Still, when investigating V/S, it decreases from -16 m/s before to -10 m/s after reaching EH630. This corresponds to a 4.44° slope at 250 kts. When descending below 1,000 ft, the aircraft starts to decelerate without a change in V/S.

Ultimately, this behavior results in a runway undershoot and landing outside the airport:

The descent indicator arrow only disappears as soon as the aircraft crosses the taxiway north of threshold 18C.