Make allowance for "Chat" plugin with "Prevent PHP execution"


basically if using the "Prevent PHP execution" feature of the "Defender" plugin,
the default "plugin AJAX" option does not work.
i appreciate that support has mentioned that "WordPress AJAX" will work.

the plugin clearly states that,
"The WordPress AJAX will be much slower and user more server resources than using the Plugin AJAX."
not just slower, but "much slower".
therefore my question/support request here is,

- is there some sort of code i can apply to still use both ?

in other word,
some sort of rule/code i can apply in an .htaccess file or by some other means to exempt the Chat plugin ?
so it seems to me that a feature of a wpmudev plugin (Defender) conflicts with another wpmudev plugin (Chat), because i cannot have my cake and eat it to
can the developers suggest a code here to allow this feature of Defender while still using the advantages of "plugin AJAX" ?

your very kind assistance in this would be greatly appreciated,
thanks again in advance,