"They couldn't even get the austere capability for A/G ops sorted in time, and how much extra are we pumping into the Typhoon programme to give it this capability?"
The official position is that the Austere air-to-ground capability embodied under CP193 (single target engagement on a single pass using EPW and Litening III) was 'sorted in time' for FOC on 1 July 2008, when the Typhoon force was declared combat ready in the air-to-ground role.
I would venture to suggest that the extra funding required has already paid for itself, since Saudi Arabia would not have bought a single-role Typhoon