Dworkin is the OP, the Mcguffin of Amber, with powers beyond the norm. He could do anything, for the Pattern is He, and He is the Pattern. Damage one, and you damage the other (which is why he went mad in the novels due to Brand and company). He could easily get the Pattern to appear in Scotland (or what the party still believes is Scotland), or as in the Merlin Tales just be there to help the real Pattern gobble up a Broken Pattern as a power-up.
Here are some quotes from the novels about Corwin's Pattern walk, which I believe at least the Veils should cause Strain rolls to keep from passing-out and dying.
“Then the thing began to curve, abruptly, back upon itself. I took ten more paces, and a certain resistance seemed to arise. It was as if a black barrier had grown before me, of some substance which pushed back upon me with each effort that I made to pass forward. I fought it. It was the First Veil, I suddenly knew.”
“I took six more rapid steps, reaching the end of an arc and coming to the beginning place of a straight line. I set my foot upon it, and with each step that I took, another barrier began to rise against me. It was the Second Veil.”
“Ten turns which left me dizzy, another short arc, a straight line, and the Final Veil.”
“Ten paces, then a swirling filigree of fire confronted me, I essayed it, my sweat vanishing into the water as fast as it sprang forth.”
“I emerged from the filigree, and marched alone the Grand Curve. The forces that shape the universe fell upon me and beat me into their image.”
“I walked three more curves, a straight line, and a series of sharp arcs, and I held within me once again a consciousness of the things which I never really lost; mine was the power over Shadows.”
From a GenCon game where each was a OP pattern sword for the sons and daughters of Prince Corwin (the PCs trapped in Corwin's Pattern).
And another quote to remember from the novels;
“Despite our major hatreds and petty animosities, we Amberites are a very family-conscious bunch, always eager for news of one another, desirous to know everyone’s position in the changing picture. A pause for gossip has doubtless stayed a few death blows among us. I sometimes think of us as a gang of mean little old ladies in a combination rest home and obstacle course.” - Corwin, “ The Guns of Avalon”