I wonder how much the non-publicly available list has been expanded since the last published one was made available? Looking through the linked document, I notice that some items that caseworkers come across frequently are not listed, such as, "What is an ESA50?"
Regarding what an ESA50 is, you could go to the Benefits & Work Publishing website and/or Benefits & Work Publishing for starters:
FIT FOR PURPOSE? A GUIDE TO COMPLETING THE ESA 50 This ESA50 form, forms part of the Work Capability Assessment, which assesses whether someone has limited capability ...
What is the ESA50 limited capability for work questionnaire? What is the ESA50 limited capability for work questionnaire? The ESA50 limited capability for work ...
Dude Swheatie of Kwug