This article is just idle speculation with some of the vague 'Russia is behind it' rhetoric we've been seeing over the past few years.

Even if someone had developed the capability to spoof military grade GPS why would they use it on a random ship for no reason? That would accomplish nothing while tipping off the military that someone had cracked GPS.

Even if this is a GPS problem at all it is more likely to be a bug in the implementation than a targeted attack.

By Occam's Razor this is likely just a plain old human error and not some sophisticated conspiracy - someone was negligent and shit hit the fan.