Can you get the Motes from the Monsterdoem if you have master rank rattlebones in it, for example?
Is it even possible to get the rattlebones from the exalted duels (as an example) as an animus?
We can't got the same drops from the creatures we collect and put into monstrodomes. The animus is like a shadow of the real monster, just a small part of their essence representing them. In the monstrodome they don't have their cheats and we can access them without questing to them or doing anything leading up to their battles (eg other parts of a dungeon).
Monstrodomes are fun and let us make our own battles, putting creatures together that don't appear in game. If we don't have membership or are below level we can get a little taster of some of the creatures we will meet in our upcoming journey...but they don't drop their 'good' items or we could get tempted to farm animus instead of the real deal and get our loot from the efforts of those who collected the animus instead of from our own achievements.
Rattlebones (rank 14) from the exalted duels is collectable using an undead enchant.
I hope this helps and you get any motes you're wanting...and that you enjoy making monstrodomes and filling them with cool monsters for fun!