As mentioned I found the issue...sort of. I do not think the drain holes under the car are blocked, when I pour water into the sunroof water comes out from them and inside.
I've used heavy duty strimmer line but can only get about a meter down the pipe work maybe to the end of the A pillar, I tried this on the passenger side too and had the same result but that one drains OK.
Im wondering if the drain pipe is broken/split or if it has a connector, if so maybe it has come off around the end of the A pillar.
The link below shows what I should probably do but I do not have the skills to remove the a large moulded piece of plastic containing loads of electrical connectors, even if I got it out the wiring is so tight I do not know how I would access the hole
https://us.lexusownersclub.com/forums/topic/88629-water-leak-into-passenger-side-floor/
The bad photo I took shows the item I need to remove
On a positive note I found a plug under the drivers footwell, removed it, stuck a wet vac over it for 5 minutes and got about 4 liters of water out of the carpet
I'm a bit stuck now and rain has stopped play....surprise, surprise