I've tried...

this can locate two strands in sandwich, sometimes i,k sometimes i,k+1 (compare 1im3 and 1bww)
[VATYFILM]-X-[CFWP]-X-[VATYFILM]

because 1eeq, I extents the pattern to:
[VACTYFILM]-X-[CFIWP]-X-[VACTYFILM]

because 1c5c
[VACTYFILM]-X-[VACTYFILMW]-X-[WLCTGQ]
[VACTYFILM]-X-[CFIWP]-X-[VACTYFILM]

seems like if these two patterns covers i,i+1,k,k+1 then...
[VACTYFILM]-X-[CFIWP]-X-[VACTYFILM]-x(1,5)-[VACTYFILM]-X-[VACTYFILMW]-X-[WLCTGQ]
[VACTYFILM]-X-[VACTYFILMW]-X-[WLCTGQ]-x(1,5)-[VACTYFILM]-X-[CFIWP]-X-[VACTYFILM]

because of 1iak
I extents the pattern to:
[VACTYFILM]-X-[CFIWP]-X-[VACTYFILM]-x(2,10)-[VACTYFILM]-X-[VACTYFILMW]-X-[WLCTGQ]
[VACTYFILM]-X-[VACTYFILMW]-X-[WLCTGQ]-x(2,10)-[VACTYFILM]-X-[CFIWP]-X-[VACTYFILM]
[WLCTGQ]-X-[VACTYFILM]-X-[VACTYFILMW]-x(2,10)-[VACTYFILM]-X-[CFIWP]-X-[VACTYFILM]

[VACTYFILMWQ]-X-[CFIWP]-X-[VACTYFILMWQ]