Ive used that and it was fine and now use DAP kitchen & bath brand (same thing diff brand) for all my thermometer probes and to close of the rest of the holes i drilled in the PVC for wires. I Love it. Hardly any smell. Not like that silicone i get from AP when I get new enclosures. Thats stuff stinks terrible and stays gummy imo. Every time i clean the enclosure the wetness makes it sticky and catches on the paper towel.
That stuff from AP is actually really good sealant. Is that Lexel? Best to use little and get it into the seam, rather than use a larger bead. It does not take much, and it is quite tough. Tougher than standard silicon.