It has been shown in our previous findings that Mo-, W- and Re-based catalysts promoted with Ni, Co, and K are considered as a promising tri-component catalyst for sour WGS reaction. In order to evaluate the stability of the formed active sulfide and oxysulfidic species at sulfided Mo-, W- and Re-based catalysts at the same surface density of the main component, namely 2 atoms metal/nm2 γ-Al2O3 support, under influence of oxidizing agents as H2O steam and CO2, the WGS reaction was proceeded in absence of sulfur in gas feed. With the intent to enable a quick check, the applied approach was to perform the WGS reaction at high reaction temperature, 400 °C, in H2S-free syngas and varying the gas hourly space velocity (GHSV). This study gave information about the behaviour of sour molybdenum, tungsten and rhenium WGS catalysts during operation accident. It was found that the active sulfide and oxysulfidic species are more stable in absence of sulfur in feed at tri-component KCoMo and KCoRe catalysts. These catalysts possess lowest sulfur dependence of WGS activity and stability of the deactivation, which is an indication of the applicability of these two systems as optimal sour water–gas shift catalysts.