(Sorry to not be inline with the stackoverflow rules. Trying to fix encryption is unfortunately a step-by-step approach and each step may take pretty much information.)

ECDHE master secret 50D5CA5D741B75B33DE31CFBCBD2EC9E285EFEDFED25E23BECE0E41E334F973D5D3171DFE54FB0834C98889868F1CB3A

Keys Seed 9C27D9EF09AF50CF0C9ABA9E535714ED07F2F522EC672A4C17FF550604F950E46E0ED5AEC5691FC199D1019ECFC1E4A8629C9ED4208DCAD30E8005C82364099C

Request Bytes 40

Client Write Key @0,48B8AE63A327BC7041B95DD59F49A5CD

Server Write Key @16,51FB049F6088FB49B406D3B5597C2E45

Client Write IV @32,6F0ED63C

Server Write IV @36,14688C2E

ClientWriteKey: 4a59ee3e8a969ed84d5358ea103b250f | ClientWriteIV: a57214b5

Are that the calculated keys from your example data? If so, they differ.