@StressedDaughter , My OH gets Tena pullups on prescription via incontinence team but when originally prescribed I was told the NHS don't give them on a 'just in case basis'. By that she meant sometimes needs , sometimes not.
I explained that although he used the toilet still he needed pull ups, as opposed to pads, because he didn't get there in time and he was dribbling making his trousers wet . So not fully incontinent.
Possibly saying mums not ' totally incontinent ' has cancelled the order! Your mum may have told the nurse she uses the toilet . I'd explain that she needs the prescription still because she leaks before getting to the toilet. I.e as she stands up. Not a full bladder empty but enough to need protection. I think the NHS give a 4 pads a day or two pull ups. I've recently asked for an additional pull up as my oh is becoming double incontinent. My nurse sent pad samples as I could have 4 of those. I'm in the process at the moment of putting forward a case for three pull ups as my oh still uses the toilet but leaks.
Hope there's some info there that might help