Repaying a Retention Bonus

I received a retention bonus from my current employer (Employer A) around 9 months ago. Let's say the sum was £10,000 which as expected was taxed at 42%, leaving £5,800. If I leave within 2 years, I have to pay the full sum of £10,000 back. At present, I have been approached by another employer, (Employer B) and they are offering a good role and to pay out my retention bonus, the full sum of £10,000. I asked employer B if they would pay employer A directly to avoid me potentially paying tax on the sum of money. They cannot do this and state they can only pay the sum of money to me. I suspect this is down to have to raise purchase orders etc and the hassle involved. My problem/concern is that if Employer B pays me £10,000 to give to Employer A, then I will be taxed on it and I will only leave £5,800. Meaning I cannot pay Employer A back within the 30 days required. I am not the intended recipient of the money, therefore do I have any options? Can I be paid by cheque and declare this on a sort of self assessment or something? If any further details are required, please get in touch. I'm really worried as the longer it takes to sort this out, I'm worried I put my potential new employer off and the role.

Hi,

The payment from Employer B would be taxable via PAYE when it is paid to you. The money you would have to pay back to Employer A may fall under 'negative earnings' and if it meets the criteria you may be able to claim a repayment of the tax through Self Assessment.

Please see EIM00800 - Employment income: calculation of net taxable earnings - HMRC internal manual - GOV.UK onwards.

EIM00800 - Employment income: calculation of net taxable earnings

Thank you.