The Titan II booster used for the Gemini missions used hypergolic fuels very similar to the Proton. (Titan II used a 50/50 mix of hydrazine and UDMH for fuel, where the Proton uses strait UDMH; both use N2O4 for oxidizer.) Hypergolics are also used to fuel Apollo service module, the LEM, the space shuttle OMS & RCS, the Souyz service module, simply because they don't require cryogenic storage and they ignite on contact, removing the complexity of an ignition system. I don't they use of hypergolics automatically prohibit man-rating. (That said, the sooner the Proton can be retired in favor of kerolox fueled Angara 5, the better. Proton burns some nasty stuff.)
I think they are, in fact, going to use the Proton. In the late 60's, the USSR was planing on using using a Proton to send a Soyuz capsule on a circumlunar flight. (Note that they weren't planing on orbiting the moon, just swinging round the dark side and heading back to Earth, similar to the course Apollo 13 used.) They flew four unmanned test flights, but they were unable to fly a reentry pattern that wouldn't have killed the crew. The plans were shelved after Apollo 8 beat them to it with their lunar-orbital mission.