I tested this in a duel against a level 50 and the resist rates for BD caster pets (bonemages in darkness line) were inconsistent with where they should be. In RvR pet resist rates should match that of their owners. In my testing I found that each pet had its own resist rate all of which were higher than the 10% of their owner. Bonecaster (level 21 spell pet) was getting resist rates of 27.50% and bone warmage (level 45 spell pet) was getting 16.50% resist rate and then I was getting 10% resist rates.
https://imgur.com/a/NpQ3axg - just SS of the combat log from a duel with another level 50, can see which pet is casting followed by the incorrect resist rate which doesn't match pet owners resist rate. To recreate just use level 45 commander with the relevant bone caster pets and another level 50.
https://imgur.com/a/NpQ3axg - just SS of the combat log from a duel with another level 50, can see which pet is casting followed by the incorrect resist rate which doesn't match pet owners resist rate. To recreate just use level 45 commander with the relevant bone caster pets and another level 50.