Custom/Conditional Column IF Date = Today then YES

NB3 , Try new columns like

new col 1 =
Switch( true(),
[Date]=today() , "Yes", "No")

new col 2 =
Switch( true(),
[Submitted Date].date = [Last Activity].Date , "Yes",
[Submitted Date].date >= [Last Activity].Date && [Submitted Date].date <= [Last Activity].Date + 1 + time(9,0,0),"Yes",
"No"
)

NB3 , let us change it a bit 

new col 2 =
Switch( true(),
[Submitted Date].date = [Last Activity].Date , "Yes",
[Submitted Date] >= [Last Activity].Date + time(17,0,0)&& [Submitted Date] <= [Last Activity].Date + 1 + time(9,0,0),"Yes",
"No"
)