So if they upgrade you for 30€, they can sell the 440€ room. If they don't upgrade you, they can sell the 470€ room. Unless they know they will absolutely sell the pool suite but not the other suite, their proposal is preposterous.
I guess they have some internal ADR goal set and therefore can't make a reasonable offer.
HTB.
You're making a huge assumption that the 440e rooms are sold out.