The moisture sensor is either open because of a broken wire or the connector is unseated. Another possibility is the circuit is shorted because of bent connector pins.
Either condition (constant open/short) will provide erroneous information about the state of the glass to the body computer, which in turn will lead to the computer directing the climate controls inappropriately. Thus failing to defog properly.
Understand glass guys are not troubleshooters and don't have the knowledge or tools to deal with the huge variety of connector types found on modern cars. Most cars didn't need to require any unplugging of any kind to replace front glass. Now they do, adding several different possible failure points for glass installers.
Installers I've seen are usually contractors operating under time pressure and with small profit margins. Any extra labor or parts needed to fix your issue would erase any profit from the initial glass job. The contractor also would likely have to eat this expense. So expect pushback and denials.
Inspect the connection to the sensor carefully for bent pins, wires pulled out of the plug, or breakage. Fix it. Failing DIY, it ought to be a one hour labor job at a local shop.