Recovery of improtant voice recording

[AC Question]

My brother deleted an important voice recording for an insurance claim my mom was going to make, she was going to use the money for my birthday. She can't make the claim and get the money. Is there a way to recover deleted voice recording files from the voice recorder app, it was deleted yesterday on a ZTE GRAND X2, With the second most recent OS of android as of august 31, 2016. The phone is unable to load playstore and the internet and I currently do not have a laptop or PC or notebook. Please answer asap