Colonel
The footnote to table 9 you refer to is not in the online edition- are you working to a printed copy? The clause you refer to did of course used to be in the 2000 edtion for sure.
See also BS5266 para 6.8.5. ( 1999 edition- not sure if the 2005 edition is exactly the same). Worth also checking the ACOP to the workplace (HSW) Regs.
BS 8300 and Approved document M are very specific about the need for a clearly visible emergency alarm cord but dont mention emergency or escape lighting. BS8300 and also refers to the need for "Back up lighting " ( para 12.4.9) and elsewhere refers to the CIBSE guide.
Codes apart, From a fire risk assessment viewpoint a disabled toilet without EL can be a higher hazard than a standard toilet without EL - for non ambulant users who have to wheel themselves in. find and apply the chair brake, find the support bars, lower the support bars, transfer themself from chair to loo, then reverse the progress. Now if the lights fail and they cant see they have an alarm cord to pull- but if theres no lights they cant see where that is either.