I can’t update Scrivener. But maybe the next best thing: I happen to have a special shortcut to toggle spell check, but it requires AutoHotKey. FWIW - if you’re that way inclined.
{ SetKeyDelay, 20
Send, !fi
Send, {Left 7}
Send, {Right 4}
Send, {Tab 6}
Send, {Down}
Send, {Tab}
;Send, {Space}
}