Umm, unless I'm seeing this the wrong way, it looks like the impeller has no blades on it anymore. If that's the case, then it certainly would be the cause. If the water isn't circulating, it will just boil.
Yeah, the old impeller was toast. There was noting left to move the coolant.
The broken bolt/screw could be a problem. It might not leak while sitting there static but turn into a geyser after the system pressurizes. I would get that fixed.
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2011 Ranger XLT, 4X4, 4 door Super Cab. 4.0L, 5 Speed M50D-R1HD, 3.73:1, 8.8" open differential, Jason Pace cap
1999 Honda CR-V EX, RT4WD, 2.0L, 5 Speed MT, 4.56:1, open differential