Well... it's true that the diamonds were mined by you. Are you throwing your friend under the bus for the xray part? Because your story about her finding the diamonds can't be true, unless she saw them from a distance and told you where they were.
You mined all the stone leading to the diamonds, and
you mined the diamonds.
LogBLock data showing all the diamond ores mined at sites #1, #2, and #3 in the screenshots below.
DIAMOND_ORE changes from player Dispyzed in the last 2880 minutes in Simplex:
25 changes found.
Page 1/2
(1) [02-24 05:49] Dispyzed destroyed DIAMOND_ORE at -30838, 9, -5569
(2) [02-24 05:49] Dispyzed destroyed DIAMOND_ORE at -30838, 9, -5568
(3) [02-24 05:49] Dispyzed destroyed DIAMOND_ORE at -30838, 10, -5568
(4) [02-24 05:49] Dispyzed destroyed DIAMOND_ORE at -30837, 9, -5568
(5) [02-24 05:49] Dispyzed destroyed DIAMOND_ORE at -30837, 9, -5569
(6) [02-24 05:49] Dispyzed destroyed DIAMOND_ORE at -30837, 10, -5568
(7) [02-24 05:49] Dispyzed destroyed DIAMOND_ORE at -30837, 10, -5569
(8) [02-24 05:49] Dispyzed destroyed DIAMOND_ORE at -30837, 11, -5569
(9) [02-24 05:49] Dispyzed destroyed DIAMOND_ORE at -30826, 8, -5569
(10) [02-24 05:49] Dispyzed destroyed DIAMOND_ORE at -30826, 9, -5569
(11) [02-24 05:49] Dispyzed destroyed DIAMOND_ORE at -30825, 9, -5569
(12) [02-24 05:39] Dispyzed destroyed DIAMOND_ORE at -30891, 13, -5510
(13) [02-24 05:39] Dispyzed destroyed DIAMOND_ORE at -30891, 13, -5511
(14) [02-24 05:39] Dispyzed destroyed DIAMOND_ORE at -30892, 13, -5511
(15) [02-24 05:39] Dispyzed destroyed DIAMOND_ORE at -30892, 13, -5510
Page 2/2
(16) [02-24 05:39] Dispyzed destroyed DIAMOND_ORE at -30891, 12, -5511
(17) [02-24 05:39] Dispyzed destroyed DIAMOND_ORE at -30891, 12, -5510
(18) [02-24 05:39] Dispyzed destroyed DIAMOND_ORE at -30892, 12, -5511
(19) [02-24 05:39] Dispyzed destroyed DIAMOND_ORE at -30892, 12, -5510
(20) [02-24 05:37] Dispyzed destroyed DIAMOND_ORE at -30895, 13, -5484
(21) [02-24 05:37] Dispyzed destroyed DIAMOND_ORE at -30895, 14, -5485
(22) [02-24 05:37] Dispyzed destroyed DIAMOND_ORE at -30894, 13, -5485
(23) [02-24 05:37] Dispyzed destroyed DIAMOND_ORE at -30894, 14, -5485
(24) [02-24 05:37] Dispyzed destroyed DIAMOND_ORE at -30894, 14, -5484
(25) [02-24 05:37] Dispyzed destroyed DIAMOND_ORE at -30894, 13, -5484
A sample of LogBlock data showing the stairstep down to site 1, and subsequent mining of the diamonds off to one side:
Block changes at -30898:15:-5486 in Simplex:
Dispyzed destroyed GRANITE
Block changes at -30897:14:-5486 in Simplex:
Dispyzed destroyed STONE
Block changes at -30896:13:-5486 in Simplex:
Dispyzed destroyed STONE
Block changes at -30895:12:-5486 in Simplex:
Dispyzed destroyed STONE
Block changes at -30894:12:-5486 in Simplex:
Dispyzed destroyed STONE
Block changes at -30896:13:-5485 in Simplex:
Dispyzed destroyed STONE
Block changes at -30896:12:-5485 in Simplex:
Dispyzed destroyed STONE
You cut that stairstep down to right beside a large diamond vein. Then you mined those diamonds.
It was the same with both other sites. No blocks anywhere near the diamonds were broken by your friend. All by you.
The tempban stands. See you in a week. A second time will be a permanent ban.