Steering rack and steering pump question

Hi,

Not sure if anyone can help me.

I have a breakdown and repair  insurance with the AA. For my Jaguar XF 2.7 2009 

Unfortunately I had to use this recently. Due to the car developing an issue with my steering.

This was diagnosed as a faulty steering rack and the garage replaced it with a reconditioned
one(not an approved AA part) after driving the vehicle for a few days I notice the steering was
still not correct.  Without going into the whole journey. Finally it was discovered by another garage that
the steering pump had now gone.

My question to the group is. The AA insurance people are telling me this won't be covered under the policy
as this forms part of the same issue and I am not coverd.
 

The reason they stated for this decision is, they tell me, When a steering rack is replace it puts extra pressure
on the steering pump and they eventually fail because of this. 

I think this is rubbish. But as I know absolutely nothing about cars thought I would ask the people who do. I know
when I had the cambelt changed last year.  The garage suggested I have the water pump replaced at the same time.
I had previously read many car owner do this and agreed.  But I don't feel the same can be said for the steering pump.

If anyone one can advise me as to this< I would be most grateful, as I don't want to create a fuss if this is what happens.

Thank you you in advance

Regards,

Gary