Hey Elliot, sorry for the delay.
How about using the PHP native function for detecting whether magic quotes is enabled on a particular setup?
http://php.net/manual/en/function.get-magic-quotes-gpc.php
If magic quotes is enabled, you can use the stripslashes_deep() call, and skip it otherwise. For example:
if ( get_magic_quotes_gpc() ) {
$value = stripslashes_deep( $value );
}
In place of the offending line:
https://github.com/elliotcondon/acf/blob/36422e64320045e665b4b98349c4d2bfda7edaa2/core/fields/_functions.php?#L188
