Why would you short Tassals *now*?, page-267

no that’s not true.

the client controls the stock lending, not the fund manager.

Large funds that outsource management will be responsible for the custody. They instruct the custodian to lend scrip and that offsets the custody fees.
The fund manager does not control this, they are completely seperate and get advised.
I was in the middle of this and it drove me nuts. I would buy a large position in a stock only to be advised it was lent out. Pain in the you know what, especially around corporate actions like rights issues, dividends and voting.