The summoning test is vs force, not force x 2. For resisting summoning drain, this would put me at :
(16 [attributes] + 7 [focus] + 2 [initiate level]) / 3 vs (14 / 3) * 2
So my ~8.3 vs ~8.7, maybe take a point or two.
Resist binding drain :
(Same 25 + 7 [edge]) / 3 = 10.7 + (10.7 / 6 [exploding sixes]), and so on... looking at about 13.
Spirit gets (28 / 3) * 2 = 18.7, another ~6 damage.
Obviously these are average, and I shouldn't depend on the dice cooperating, but with a few other preparations it wouldn't be so bad. A triggered heal after the summoning to reset my damage, plus boosted will and charisma, as you suggest, give excellent odds.
Good enough that I'd chance it? Probably not. I'm thinking of dropping to a force 10, as I could feasibly bind one in about 3-4 months. But it is possible, without relying on burning edge to survive.
If the spirit were unwilling and using its own edge to oppose me, it would definitely be a different scenario. I've failed to mention that I've had previous GM-sanctioned contact with the spirit, and the alliance is a mutual goal. I should expect no bonuses to my summoning and binding rolls, but neither will they be actively attempting to kill me.