I agree that the chance that Innes says something very stupid is not high, but I see what you mean. Then of course I can see Hayden having that much confidence in Innes so that he would allow it.
OTOH, him as the prince not travelling to the other countries could be seen as bad form as well. Like, "You don't trust us, why should we trust you then?", that kinda thing. Of course Innes should look out for his safety as the oldest heir, but still... it does sound a bit... let's say, cowardly? I wouldn't think that Innes would let that keep him from doing what he has to do and that is rebuilding Magvel. I don't feel that it fits with his characterization, you know.