Late oxygenation is never a good idea. Firstly it should not be necessary, and if your fermentation stalls that is indicative of a problem that aeration won't solve. Secondly, high levels of oxygen and low levels of fermentable sugars may push your yeast into switching from fermentation to respiration, which produces acetic acid (vinegar). Thirdly, oxydation reactions will almost certainly cause off-flavours which can't be corrected.
I would suggest a more regular approach to try and restart a stuck fermentation, such as the one outlined here. Post-pitching oxygenation should be considered only as a desperate last-ditch alternative to throwing the batch out (i.e. if throwing it away is your only other option you may as well go for broke and try it).