This was WI's lowest score in an innings but not the lowest in test by any means.
That record goes to NZ - 26.
Details here from cricinfo
Interestingly, the lowest BD score of 87 is still higher than the lowest scores of all the other test playing countries.
Lowest Total for each Test Country
26 New Zealand v England Auckland 1954/55
30 South Africa v England Birmingham 1924
30 South Africa v England Port Elizabeth 1895/96
36 Australia v England Birmingham 1902
42 *India v England Lord's 1974
45 England v Australia Sydney 1886/87
47 West Indies v England Kingston 2003/04
53 *Pakistan v Australia Sharjah 2002/03
63 Zimbabwe v West Indies Port of Spain 1999/00
71 Sri Lanka v Pakistan Kandy 1994
87 Bangladesh v West Indies Dhaka 2002/03
* One or more batsmen absent or retired
We haven't played enough
- Z