If fifita is the incentive here than I'd pack Sam's bags for him. Yes he is great but has hands like feet and his 2 younger brothers are going to be better.
I think we can agree to disagree on Fifita vs Sam.
You need to keep you focus on Eels players retention vs Souths.
As for the Souths fans who do state that Sam would not leave because he loves Souths and Sydney. Perhaps , however if $2m a year offer is halfway true , then Sam is gone. He can always come back to Sydney to live and with a healthier bank account to boot . In addition for a proud Englishman , there would be an attraction to play for England in Union , which has a much higher international profile than playing League .
If this offer is real and Sam request a release , then I believe Souths should release Sam from his current contract by way of a conditional new contract , which ties Sam to Souths should he return to Australia/NRL in the future .
As for Fifita , Souths would be in the line with most other NRL clubs and Union to sign him.