He will be dismissed due to capability. Not made redundant - because he isn't, he's incapable of doing his job/coming into work.
Then they will consider the Occy Health recommendation as to whether he will be capable of working again in the near future, the medium term or ever again. And decide whether he should receive nothing other than accrued holiday and last salary payment (probably about five grand...) or if he should get Tier 1 or tier 2
The LGPS states that ((4) A member is entitled to Tier 1 benefits if that member is unlikely to be capable of undertaking gainful employment before reaching normal pension age. (5) A member is entitled to Tier 2 benefits if that member is likely to be able to undertake gainful employment before reaching normal pension age.”
He should be attending a dismissal hearing once the report is received, preferably with a union rep and should be aware that it's possible that they would decide he could get better again and be able to collect trollies in a supermarket car park or do office cleaning a couple of days a week, even if he isn't likely to be able to do his original role anymore.
for example, Edinburgh council's terms are
If it’s decided following an Absence Meeting 3 that there’s nothing more can be done to help you return to work, or that your short term absence levels are no longer sustainable, then it’s possible you will be dismissed on the grounds of capability due to ill-health. This decision would only be taken after all mitigating factors, reasonable adjustments and redeployment possibilities had been explored. Note that Absence Meeting 3 can only be held by a senior manager with the authority to dismiss. If you are dismissed on the grounds of capability due to ill-health, you will receive payment for any outstanding annual leave you have, as well as payment in lieu of notice.
Ill-health retirement (pension scheme members only)
If you are a member of a pension scheme (LGPS/STSS), below normal retirement age, and advice from Occupational Health is that you are permanently unfit to carry out the duties of your post, you may be dismissed on the grounds of capability due to ill-health with access to pension benefits. This is known as illhealth retirement. The pension benefits you would be able to access through ill-health retirement will vary depending on whether, according to medical advice gathered by Occupational Health, you are likely to be able to work again before your normal retirement age. Details of the relevant pension benefits levels are outlined in the Sickness Absence User Guide.
https://www.edinburgh.gov.uk/downloads/file/25965/sickness-absence-policy#:~:text=Capability%20dismissal&text=If%20you%20are%20dismissed%20on,sick%20pay%20has%20run%20out.
I'd be very suspicious, because it is not common for somebody to be granted full, never going to be able to work again for the rest of his life, Tier 1 benefits for anxiety and depression.