The problem is, that MatrixForm, which displays Acc.schedules is clumsy enough already “by design” to tamper with it furthermore. It is next to impossible to do such modifications to MatrixForm.
If it was easy achievable, there would be all this included in standart. Hiding colums --never mind, in code or manually, as in ListForm-- is one unsolved problem, another boring unsolved case is impossibility of filtering rows by value. The last has been asked here in forum many times - how to hide “empty” rows…
Analysis by Dims, when exported to Excel, create Pivot Table, when you can play with it as you wish - filter, add hierarchical subtotals, etc etc, you name it.
Acc.schedule is built internally in a different way, it is exported as flat Excel sheet, but even there you have some limited Excel features to filter the result.
Maybe export to Excel as described is usable for you, and it is by no means easier and far less expensive, than trying to modify MatrixForm. Many have tried, as it really has these serious shortcomings you and other forum readers before you complained about, but I haven’t heard about a successful solution up to now (BTW at least 10 years…)