I'd suggest figuring out the Windows casting issue. My TV is hardwired to the network, so maybe that helps.

Here's a script for a mode switcher. Works great using psexe to wrap it in an executable.

Do {
    CLS
    $Mode = Read-Host "`r`n(W)ork, (P)lay, (M)ovie?"
    } until ( 'w', 'p', 'm' -contains $Mode) 

if ($Mode -eq "w"){
# Work Mode
displayswitch.exe /extend
# Display taskbar and restart Explorer
$p='HKCU:SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\StuckRects3';$v=(Get-ItemProperty -Path $p).Settings;$v[8]=2;&Set-ItemProperty -Path $p -Name Settings -Value $v;&Stop-Process -f -ProcessName explorer
    }

if ($Mode -eq "p"){
# Play Mode
displayswitch.exe /external
# Display taskbar and restart Explorer
$p='HKCU:SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\StuckRects3';$v=(Get-ItemProperty -Path $p).Settings;$v[8]=2;&Set-ItemProperty -Path $p -Name Settings -Value $v;&Stop-Process -f -ProcessName explorer
    }

if ($Mode -eq "m"){
# Movie Mode
displayswitch.exe /internal
#Hide taskbar and restart Explorer
$p='HKCU:SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\StuckRects3';$v=(Get-ItemProperty -Path $p).Settings;$v[8]=3;&Set-ItemProperty -Path $p -Name Settings -Value $v;&Stop-Process -f -ProcessName explorer
    }