Fries Rearrangement Products
The above is the mechanism for Fries Rearrangement for a brominated ester( doesn't matter really, for any ester the mechanism essentially remains to be the same).As per what I infer from your question, I think you mean to ask why even in the presence of $\ce{O^+-AlCl3}$ which is a strongly deactivating group, the major product is not meta-substituted.
As you can clearly see, in the next step itself a stable acylium is formed and the formal charge on $\ce{O}$ is no longer positive.So, as phenoxide ion is an activating group and o,p-director, two possible products are expected which are ortho and para substituted.However, at higher temperatures, the major product is ortho substituted which is driven by chelation.
NOTE:
As far as I know, both intramolecular and intermolecular reaction mechanisms are able to explain the major products and it is still not confirmed which one is the actual mechanism.
Image source:
https://www.synarchive.com/named-reactions/fries-rearrangement