Chris Snee didn't officially retire until after 2013 season. He was IR'd during Summer Camp so that he could collect the money he was owed.
We can debate on whether that was because Coughlin was his father-in-law or if it was the Giant's were just rewarding him for being an excellent Giant for his entire tenure, but they didn't have to pay him that year, and they surely could have cut him before it ever got to training camp.
On that note, this year is a year where we are eating a ton of dead cap to free up space for next offseason. Eli got his $5 million dollar bonus. If for some reason, we could trade for Rosen (I'm not advocating for it), or draft a QB of the future that's ready to play (doubtful on this option), it doesn't mean we necessarily have to stay with Eli. Eli is probably more tradeable at this point as we probably eat the bonus.
I don't think it will happen, just wanted to point out that we have paid Giants Legends for being good soldiers before, and it could possibly happen again.