Hi, Rosana.
The audit is ISO of what, btw? and if ISO 22000, what is the main difference is FSA audit meaning what clauses are excluded or added?
From the perspective of CCP, which in basic terms, is to eliminate, reduce hazard to an acceptable level. Which this may mean that "whatever is within" of what you receipt (of there is a single cell or heavily contaminated by a pathogen), the <-26C will not likely help eliminate or reduce it to acceptable level, it will help the process to remain it as inactive. That is why storage temp most of the time is referred to as PRP.
Now, depending on the decision tree you have used, there are some qualifications for CCP such as feasibility to be monitored, with certain criteria (numerical limit) and if it can be monitored it can also demonstrate that action can be taken immediately when this limit is exceeded. I assume that if any case, on any monitoring, you temp became higher than -26C, you will not immediately throw the product (or reprocess or resort depending on the process). Which is why it may not qualify as CCP.
On other aspect, validation is also key. Is your spot the warmest spot, or is your monitoring location may also tell you if it correlated to your meat core temp?
Many factors will play if you tag it as CCP. :)