Bottom of the Barrel Valuation, page-35

Reservoir pressure - 6,746 psia (6,732 psig)
Kinga depth - 4,817-4,871m MD.
Hydrostatic pressure = depth (ft) * 0.052 * fluid density (ppg)

Depth of fresh water required to kill well? Fresh water = 8.34ppg
6,732psi = depth (ft) * 0.052 * 8.34
Depth (ft) = 6,732 / 0.052 / 8.34
= 15,523ft = 4,731m

We can also estimate the density of the fluid column that did kill the well. (assuming TVD matches MD).
Wireline discovered a fluid level at ~250m below surface after perforation, plug, N2 lift, retrieve plug. (approx. fluid depth = 4,567m)

6,732psi = 4,567m * 3.281 * 0.052 * fluid density (ppg)
Fluid density (ppg) = 6,732 / 4,567 / 3.281 / 0.052
= 8.64 ppg

SE-3 does appear to flow - both water and gas - but one or more perforated zones are flowing enough water to kill the well.
Moving contractors to SE-2 allows STX to plan further works at SE-3, AND allows them time to source the required equipment and personnel.