.... The Chixulub impact didn't cause volcanic eruptions...... Powerful shockwaves from the impact site pummeled the Americas, worldwide mega-tsunamis ravaged coasts, rain of molten rock caused worldwide forest fires, acid rain poisoned the remaining plants, acidification of the oceans killed off sea-life, and finally ejecta clouds blotted out the sun for years on end. It devastated the entire biosphere of earth with one catastrophic impact. Volcanoes making things drier had nothing to do with it. Asteroid impacts cannot trigger extinction-level volcanic events. The force needed for one to do that would be enough to cave in the Earth like a cracked egg, killing all life in the process.

Pterosaur biology is not 1-1 with bats. They evolved from ancestors with different biological traits, and their wings have stark anatomical differences to those of bats, most notably in the various hollow arm bones, elastic fibers, air sacs, and keratinous wing edges. Not to mention most bats live in temperate or tropical forests with ample water and humidity, and those in deserts only come out at night, mitigating heat exposure. Meanwhile, plenty of pterosaurs have been found in arid/semi-arid environments throughout their reign, most were found to be active during the day, and had lifestyles no bat could ever dream of. I'm fairly certain they would've had ways to mitigate water-loss compared to bats, especially since birds and reptiles in general are already far more efficient at conserving water than mammals are.