.htaccess problem with redirecting 1 domain in a Multisite

I'm trying to come up with the correct .htaccess syntax to create re-write rules for different domains in a multisite using sub-domains. Every rewrite rule I try to create effects all sub-domains. For example- If I try to redirect domain4.com/events to domain3.com/home, If domain5.com has an events page it is also redirected to domain3.com/home or in some cases it returns a 404. I've not been able to create a redirect in my cPanel that works either. Can someone suggest the right rules that would effect the redirection of a URL in only 1 domain or maybe some other method to achieve the same results . The ideal scenario would be to redirect any URL in domain4.com to the home page of domain3.com.