Based on the two studies by the CIVC of the [multi-year, 3-5] storage of Champagne, the 'pegging' of Champagne corks is more likely to be caused by the nature of Champagne and the length of time the wine is in contact with the cork - and, therefore, on the orientation of the bottle.
In other words it was whether the bottle had been vertical or horizontal that most affected the shape of the cork when it was extracted. Bottles stored standing up more readily assumed a mushroom shape when extracted whereas those lying down were often 'ankled' or 'narrowed' which I assume is what 'pegged' means.
The most important conclusion of these studies was, unsurprisingly, that temperature [keeping the wine below 15oC] was key to the storage of Champagne and extensive tasting of the wine [3000 bottles stored in 4 different paces both standing and lying down] at the end of the study periods did not show any material difference in the taste/quality of bottles from either orientation - although the corks and their mechanical properties certainly did.
I have no idea whether refrigeration might affect the cork [more or less] but based on those studies it seems unlikely. However the wine would at least have been kept well below 15oC!
In any event, on the assumption that the wine in the refrigerator wasn't being kept there for the 3+ years [of the CIVC studies] but for a more normal pre-consumption period it seems even more unlikely that the temperature [and more likely the wine itself] could cause 'pegging' in a short period. And if it was being stored in a refrigerator for 3+ years it seems that the 'pegging' would be due to the orientation of the storage.
OTOH I am sure most of us have observed 'pegged' corks extracted from older vintage wines that have seen extended cellaring without any deterioration in the contents or loss of pressure in the bottle.
Refrigeration=pegging=oxidation therefore seems an unlikely equation.
OTOH might an excessively long refrigeration period affect the closure properties of an old, already 'pegged', cork?
