School finally not able to provide dining facility for its staff? (4,5)
I believe the answer is:
high table
'dining facility for its staff?' is the definition.
I know that 'dining' relates to this answer.
'school finally not able' is the wordplay.
'school' becomes 'high' (high is a kind of school).
'finally' says to take the final letters.
The final letter of 'not' is 't'.
'high'+'t'+'able'='HIGH TABLE'
'to provide' acts as a link.
(Other definitions for high table that I've seen before include "seats of honour" , "At which fellows served" , "Elevated dining area" , "Where the principals dine" , "dons scoffing here?" .)