They could very well have been doing 180 knots indicated with a 30 knots tailwind at that stage.
There are enough data points quoted in the CIAIAC report to make a reasonable estimate of IAS at that point (3.8 DME), say 195-200kt:
6nm - 232kt GS
5.7nm (FAP) - 215kt IAS
3.8nm - 210kt GS
THR - 155kt IAS
Surface wind is quoted as 2-3kt southerly, and wind at the 6nm point (say 1900') as around 10kt northwesterly.