Flashed a secondhand iPhone 6s only to find that it is still linked to previous account?

[SaturdayNight]

Long story short, I recently purchased a secondhand iPhone 6s. However, the original owner was still logged into iCloud, had forgotten her password, her email had been terminated (it was a former work email) and the account has 'dual security locks' between her and the company which originally purchased it, as it was a work-related phone. As a result of this, I could neither log her out nor factory reset the phone.

Being impatient and stubborn, I decided to use 3uTools to flash the phone in an attempt to bypass this issue. While I was successful in resetting the phone, it is still linked to the previous account and now I can't use the phone at all without the previous owner's iCloud details, which I still don't have access to.

I'm just wondering if there's anything I could do from here in order to somehow get into the phone and then avoid this iCloud issue?

Thanks guys.