Mistake on Josekipedia after probe & invasion on keima shimari?
White Q19 is a mistake.  The correct move is R18.  Then Black can't connect at Q19 because the stones would still be in atari.

$$c White survives!
$$ ---------
$$ ..63512.-
$$ .XXOO4OO-
$$ .XOXOOX.-
$$ ..OXXX.X-
$$ ......X.-
$$ ........-


After the capture, a and b are miai to make White a second eye.

$$c Resistance is futile!
$$ ---------
$$ ..Oab.O.-
$$ .XXOOOOO-
$$ .XOXOOX.-
$$ ..OXXX.X-
$$ ......X.-
$$ ........-