Hi jiljilbean,
Cheese & it's microbiology are not my area and I'm sure other members will be able to provide more detailed answers. However a google confirms my suspicions that the presence of certain yeasts in high enough populations can affect the quality and cause spoilage.
Yeast spoilage may also lead to detectable but non-visible alterations resulting in off-odor and -flavor or texture alterations through the production of ethanol, CO2, and volatile organic compounds (primary and secondary alcohols, aldehydes, esters) as well as the production of lipolytic and proteolytic enzymes (glycolysis)
It was defined that yeasty and fermented off-flavors were detected when yeasts grew at populations equal or above 105–106 CFU/g
https://www.ncbi.nlm...les/PMC5620633/
Yeasts and molds may enter cheese from a variety of sources, including the starter culture, ambient air, brine, processing equipment, and workers [5, 34, 39]. Many yeasts can contribute to taste, flavor, and appearance; however, not all species produce beneficial effects, and a species may benefit one cheese while spoiling another. Particular yeasts on the surface of the cheese can cause spoilage or generate undesirable aromas, flavors, or other metabolic products that reduce the quality of cheese [2, 4, 23, 50]. Furthermore, while yeasts are rarely associated with foodborne infections, studies have shown the presence of medically relevant yeast species in various cheeses, including Candida albicans [11, 51], Candida tropicalis [13, 51], C. krusei, and C. glabrata [51].
https://digitalcommo...=foodsciefacpub
Can I ask what type of cheese is in question here?
Also, just one thread for the topic would be sufficient 
