it is unclear to myself how they dry the THF in KOH
I believe stirring them together overnight, following by decanting is the procedure, as KOH hold less water at higher temp.
can NaCl be used in replace of sodium wire??
No way...
And you are correct about the "ketyl pot". It is further described in https://www.thevespiary.org/rhodium/Rhodium/chemistry/equipment/benzophenone.ketyl.html (https://www.thevespiary.org/rhodium/Rhodium/chemistry/equipment/benzophenone.ketyl.html)