To go with your angle tho, a sprinkler head is a one-time use item; they are never tested, whereas a shower is tested weekly. Sprinkler heads are irrelevant since they would never be tested, wouldnt be within 2' of the shower, and would never be in the way of access to the shower. Furthermore, under a fire condition, saving lives is more important than turning a previously dry location into one that is sopping wet from an activated head, and the FD may/is gonna blast it with a fire hose anyway. That is an extraordinary circumstance. Testing emergency showers weekly is NOT an extraordinary circumstance, it is (supposed to be) a weekly occurrence. Some area within the field of a shower *should*, imo, be classed as a wet location.
Consider it like this: we have working space clearances around panels, so that we can safely access and work on them. Eyewash stations/showers *should*, imho, have the same clearances so they can be safely accessed when needed. You cannot put any obstructions between a potential source of harm and the station. In some environments, like containment pits or pump galleys, the station is stand alone since there are chemical dangers all around.
The OP's switch at ~2' away. I keep asking if the switch is needed to illuminate the shower area because if it is, I believe that a violation of OSHA rules. Also, a nearby (< 2' away) bell box on a concrete wall containing a switch *may* be within the field of the weekly shower test spray. It could also be a "protrusion or sharp object" too close to the shower.
Without more information from the OP (a picture would be great) re: how close the switch is to the shower, its height, etc. we will never resolve this. There may be more than one factor at play: wet/dry location, the potential safety aspect of having something too close to the shower that doesnt belong, and having to actuate other equipment in order to use the station.