Loaned Coliseum units don't scale ability levels

The loaned units scale level with the lowest owned unit. In my case all my units are level 45. My loaned vader's abilities are not scaled to his level 45. At level 45 (Which he is), his abilities should be level 6 just as the other units. If this isn't a bug it should be stated in game that loaned units don't upgrade their abilities, which doesn't really make sense.