Roscoff to Cork ferry May! Anyone got space for a dog in car! If not advice for travelling with dog

So yea, I am moving back to Ireland in summer from Brittany France. There is a perfectly cheap ferry taking me from near where i live in france to where my destination in Ireland, the pain in the hole is they won't take foot passenger dogs despite having a kennel apparently on board becuase its only accessed through the garage. i tried my best ringing them about it but idk, the world would collapse if a foot passanger walked into the garage to leave the dog at the kennel. You have to have a car for dogs they said.

Anyone willing to take me on as a car passager and my friendly collie ? Anytime in may-june works and i'll pay my part and extra. Otherwise I am quite at a loss, more expensive and more complicated travel plans between airports and landing in Dublin.

Any other advice welcome :)