This work investigates the linewidth enhancement factor (alpha-factor) and stability of an optically-injected InAs/InGaAs quantum-dot Fabry-Perot laser. Using the injection-locking technique, the above threshold alpha-factor is measured to be as low as 0.6 at 1.3X the threshold current. The below threshold alpha-factor is also measured using the Hakki-Paoli technique. The measured alpha-factor values are used to simulate the dynamic response (stable locking, period-one, period-doubling, or chaos) in the context of single-mode rate equations under zero-detuning injection conditions for external injected power ratios ranging from -11dB to +15dB and slave current bias levels of 1.3X, 2X, and 2.6X threshold. Legacy literature has shown that optically-injected diode lasers typically follow the period-doubling route into a chaotic region as the injection level is increased. Simulations show that at 2X the threshold current, a small region of period-one operation will be observed followed by stable-locking as the injection ratio is increased. This predominantly stable behavior is driven largely by the low alpha-factor. Experimental results support this prediction, where under zero-detuning conditions, only unlocked and stable-locking operation is observed. Experimentally, periodone operation was not observed at a slave laser bias current of 2X threshold, as it was predicted to occur below an external power ratio of -20 dB, a level which was not attainable in this work. Such findings suggest that a quantum-dot device can be employed in an optically-injected configuration for photonic tunable-clock applications.