Has she still got legal capacity?
She can have "mild" dementia and still have legal authority.
That is the first thing you need to ask the doctor to make a judgement on.
The doctor will supply a letter/ medical opinion which her solicitor will need. If she has she needs to sign a Enduring Power of Attorney and appoint someone to act for her when she can't.
If she no longer has capacity it can be more complicated.
Apart from money most agencies will work with the family ( >> once the family are in agreement<< ), while it may be a little unfair its best if only one or two people get involved in communicating with key decision makers so that there they can build a consistant ongoing discussion of what "the plan" is.
The other thing is her pension if it is being paid into a bank ac she will loose access to the account once the bank realise she has no capacity. If she collected it herself at the post office she needs nominate someone.
Try call alzheimers society who may be able to hepl direct you to getting support.
alzheimer.ie/
If you post in this board you may get better local knowledge
www.boards.ie/categories/carers-caring
She needs a care assessment
www.hse.ie/eng/services/list/4/olderpeople/
You should phone the community health center
[ keep clicking down] www.hse.ie/eng/services/list/1/lho/
and find which public health nurse is in charge of doing the assessments. Why is the OT doing the assessment? No disrespect to the OT but my understanding is that funding etc is managed via the PHN doing a holistic report which OT and physio etc supply parts. The OT can be very valuable recomend, get equipment etc but there may be a incontinence nurse who can help too. If she needs pads etc i believe the PHN can supply some.
In this case you could also ask for a physio to do an assessment of her physical condition to see if soft exercises (pelvic floor) would make her feel more confident when moving around.
www.hse.ie/eng/home-support-services/after-you-apply-the-care-needs-assessment/after-you-apply-the-care-needs-assessment.html
If she now has a carer, you can use that to your advantage.
Make sure that the carer documents their interactions what she can not do, if she is a fall risk etc
And NB that she is refusing to allow family members to help. Sometimes people will behave better for carers and they remove the stress and conflicts involved in doing simple things.
If the carer has experience they are quick to find a method which works with her personallity.
If they are part of a company contracted by the HSE they should have done a full care assessment and have written up a care plan. Have a look at that and see if includes all the points. The company have an ongoing relationship with all the community services needed so (case managers) can also be an invaluable source of information.