No, that makes no sense at all. Clubs might pay a player to leave when they just want to get their wages off their books, but not when they are one of their best assets and moving on to a bigger club. If Donny said, "we will pay you £500k to leave", Saints would say "hang on, we're not paying £3.25m if you are willing to accept £2.75m". It's a complete nonsense.
If they were desperate for the cash they would accept Ipswich's bid as well.