So sorry for the situation in which you and your husband find yourselves and at such a young age. If your local consultant feels it would be best if he was treated in England, I would ask who he feels he could recommend. If all your husband's histology with scans and other tests are passed over to the more experienced consultant in England perhaps a telephone appointment might be a good way to start.
I don't know how the set up for treatment in England would be affected by your being in Northern Island as regards the NHS but this is something you will doubtless ascertain if you don't already know. Naturally, you will both want the very best treatment possible but not overtreatment and this will be discussed with your new consultant in England.
Do let us know how this goes.