Probe not working on maverick et733

I put two pork roasts in my cabella smoker. I put a probe in a clip on the grill and a probe in one of the roasts. The probe on the grill looks like it is reading correctly between 220 and 230 degrees. When I put the probe in the roast it initially read 259 degrees. In the last half hour, it has raised to 262 degrees. My wife washed the probes last time we used them and I warned her about letting water get into the probe. If water gets into the probe, will the probe stop working, or will it give false readings? I switched the probes between 1 and 2 and got the same readings. Thanks