You're very welcome, hope your dad is pleased. I've enjoyed doing this, I love looking at old maps and trying to figure out where things were.
Edit - I've found a better map of Tees Iron Works on the Old-Maps website. Search for Dockside Road, then choose the Cochrane's Wharf address. From the old maps on the side, scroll down to the 1894-1895 Pre WWII 1:2,500 Yorkshire map. You will see Tees Iron Works and Ormesby Iron Works in close up.
I can't see Tees Cottages marked, but the address that appears next to that in the 1891, Cargo Fleet Timber Yard, is clearly shown, so presumably the cottages must have been somewhere around there, and there are some unmarked buildings dotted around so maybe one of those is the cottages.