Your demo app refers to a Dashboard.csv that no one will have access to.
If you google that error message, you'll see it has to do with DT. But it's hard to diagnose things without being to setup Dashboard
Could you format this into a reproducible example? That is a set of code or rstudio.cloud project that folks can easily get up and running to replicate your issue? Currently, this is only part of a shiny app.
IF you aren't familiar with best practices for shiny reprexes, check out
This will make it easier for folks to replicate your issue and offer suggestions to solve it.