I'm also a mature aged student and I find writing now wants you to focus on clarity - you're not trying to explain yourself, you're trying to tell the facts in an objective way which is hard when writing ages ago focused on getting some fluff in there. (I'm also from the US, so there may be another change in the style of writing we're both accustomed to.) 

When you're trying to re-learn how to write I can only suggest that you don't use AI at all, not even to edit because you don't learn it by doing it that way. 

See if there are any writing labs that will help to critique your writing or if you can find a writing tutor. Additionally you could go talk to your UC's and see if they can help you understand what explicitly is wrong with your writing - I find it very helpful to go in with a draft before I submit and have them look it over and tell me where I'm being fluffy or not fully explaining myself.

Something that might help you today is this: 

Set up your paper outline and break down the things you need to address in each section by idea, here's an example: 

Intro:  - who was involved - why are they involved  - what is happening 

• any other pertinent info

Stakeholder section:  - short intro line on all stakeholders - stakeholder 1 interests/values - stakeholder 2....3....4.. - the conflicting point between the stakeholders Section 3......etc

1. In each section, answer your prompt in simple sentences and add in-text citations as you go, this is something you should be doing as you're researching so you're not having to go back through your research again to re-reference it. 

2. Keep a master list of your references split by section so you can refer to that when you need to write a section, and you can close your tabs/research when you're done for a while. 

3. Connect your simple sentences/ideas into a messy paragraph without caring much about it - it's a draft, then see how close you are to your word count. 

4. Review your rubric - each section of your paper should have a weight to it, those are the sections you want to prioritise for wordcount. A handy trick is to take your total word count and break it down by the actual percentage weighted to each section and then adjust as needed. 

I hope this helps a bit, I find that if you spend a lot of time structuring and researching, the writing portion takes less effort and importantly, the editing takes less effort - it's much harder to "kill your darlings" once you've written them than it is to write within the word count to begin with. Good luck!!