No, I did not find some kind of weird unblockable that Guile has. However, I did acquire a large mass of sodium from a local Evil Ryu player. I think that it would be important to catalog all the unblockables that other characters can do against Guile, however, and find the best way to recognize then escape these various situations.
It would also be interesting to find answers to “hard-to-blockables” as well. Any input from everyone is appreciated.
f.throw into corner > dash > c.mp > j.mk
b.throw > hop > j.mk
Escapes: Crouching, last second block
shoryu xx FADC > hk axe kick into corner > sweep > j.hk
Escapes: Wakeup empty neutral jump, “just guard” away from corner
f.throw into corner > taunt > j.hk
b.throw into corner > s.hp > j.hk
Escapes: Neutral jump, back/forward dash, possible focus dash
neckbreaker > walk forward > s.lk > j.lk