Not sure where you got that chart or how old it is, but it’s rubbish, especially for a team like Philly. NFL teams convert just under 50 percent of two-point conversions. Kickers miss about 6 percent of extra point kicks. The math favors going 2 almost every time.
In this case, the downside is minimal and the upside is big: go up by two scores if you convert, and even if you fail, you’re still up by 7 and GB will at best tie you if they score another TD.