Pip assessors report

Hoping someone can help with this question.. My son had a pip telephone assessment recently and received PA4 which only awarded him 2 points for needing prompting to engage with others. He previously scored 11 points in 2018.
The hcp rushed his assessment and didnt ask what his day was like, nor did he write everything down that was relayed. The hcp basically said because he was now working 35 hrs per week he didn't have any MH issues and went on to say "why do you need CBT when you are working full time" when my son said GP had referred him for CBT a number of weeks ago.
My son still struggles with anxiety and low mood and although he works hybrid mainly (admin job no customer contact) he continues to need and received a lot of family support, The assessor mentioned in one part of his report that medication was stopped due to poor effect and that as CBT was a number of years ago, then basically he was fine now. But has acknowledge he has anxiety hence the 2 points for engagement. However, he has not considered anxiety in any of the other activities at all, and basically says not relevant as has had no specialist input since 2018 or memory clinic input. and he works full time. He has started his fist job in march of this year and purposely choose a hybrid position so he could cope with working.
There is no reason for memory clinic input as my son did not indicate that he had significant memory issues and surely a memory clinic is for suspected dementia ? My son did indicate that due to excessive anxiety, he had difficulty sleeping which resulted in poor sleep and therefore this impacted his mood, motivation etc. The reason he works hybrid is because he can work from home, in his own environment without distractions etc.
I find that this hcp report is flawed as he copied and pasted the reason for each zero points in each activity due to my son being in full time employment, no medication and no specialist input since last assessment.. Prior to this review assessment he was at university. So, my question is how can the hcp make such a difference between someone studying at university and working and therefore zero points being awarded. Also the assessor did not mention lots of the information given to him and omitted relevant information from the report.
He also mentioned further evidence dated 2020, and I know nothing about this whatsoever as I always keep records of what I sent. There was no pip assessment since 2018, wo what evidence dated 2020 is he even talking about I wonder?
I see inconsistencies in his report, such as the time finished differs by 11 mins according to phone record.
Any advice appreciated as I know this will likely be a refusal by the decision maker.
Sorry for the rambling!

Thank you kindly for your reply... much appreciated indeed. My son is still waiting on the actual decision from the decision maker, at the minute he has only received the PA4 which is the assessors report which clearly only says he meets description 9b. engaging with other people. need promoting and encouragement.
So, basically it is very likely the decision maker will indeed award the same points based on the assessors recommendations.
So I'm trying to prepare ourselves in advance of this dreaded decision.
Yes you are correct the assessor did not record everything that my son explained. However, we did record the telephone assessment ourselves and did not tell the assessor this (i believe it is not a legal requirement to inform the assessor as it is for personal use) However, can we use extracts of this recording as evidence when we challenge the decision. Such as the decision maker did not make note of the following: x y z which clarifies clearly the difficulties my son has. etc - can we refer to the recording??
Would getting my sons patients records for the day he seen the GP and was referred to CBT help his case, or do I actually need this as evidence. I'm concerned as the decision maker could say we just made this up.
Thank you