Decipher the script in PHP

Employer
[no-member:pro]Vladimir[/no-member:pro]
Project parameters
Type of cooperationOne-time project
SectionWeb development, Web programming
Prepaymentwithout prepayment
Payment methodsBank transfer, Electronic money
Acceptance of requestsfrom Mar 12, 2019 until Mar 17, 2019
Project description
He ordered the development of the script on a paid basis. The developer agreed on installment payments, after which I will receive the full version of the script with all decrypted files. The script did not use for almost 2 years, but when it was needed - it turned out that the developer threw me still not the full version of the script at the end - 2 files remained encoded, which were tied to the date. The developer’s contact is lost and from the script for which he paid a lot of money, now it is worth 0. Who can help decrypt these 2 files and remove this verification?