No fee credit on partial refunds

Today I refunded an buyer for one damaged item in a set. It was a partial refund. eBay refuse to give me a credit as they say they only issue credit fee on full refunds for people on Managed Payments. I was happy using PayPal, but it was eBay who forced the change to MP. The only option therefore is to request the return of the items as eBay prefer to credit fees on a full sale price, than to credit fees on a partial refund. 

 

Anyone else had this experience? What are the other options?

 

Also only just found out the selling fees are now 13.4% not 10.9% any longer.