You need to be careful comparing the breaks made by english-billiards players in different eras because the rules change. In Lindrum's day there was no limit on the number of consecutive cannons that could be made. Lindrum and others were able to master the nursery cannon and use it to build big breaks. (The all-time record, using a particular type of close cannon before it was banned, was a little under half a million!)
But modern players have long played under rules that limit you to 75 consecutive cannons (150 points) before pocketing a ball.
Tom Reece ran 200 thousand by "jawing" the balls in a corner and they made a rule against that. You are correct that Walter was the master of the nursery cannons but there is some video of him pocketing balls also and he was to say the least, a formidable shot maker.
Walter was the first to break the balls to a certain place to set up long runs.
How did I forget Lindrum in my list?