I've spoken to the behaviourist at the Rescue centre, who says he is a lovely dog, and believes it is highly unlikely that the little chap would want to be top dog. She actually fostered him for 4 weeks to help with his 'issues' , but couldn't keep him as she already has 3 dogs. He has several issues, but the main one is that he is suffering from stress, and is currently on rescue remedy. Apparently he was bought from a pet shop, and has been pulled about by children. He has been rehomed twice, but returned, in her view because they didn't follow the advice given by her and the centre.He is now crate trained,which appears to help with his separation anxiety. The poor little mite seems to have been through a lot. She suggested that we arrange for Boysie to meet him, and see how we get on from there. So, I'm going to try and arrange to see him next weekend .
Thanks for all the helpful advice.