If you're finding your company web forms are routinely quarantined as spam, there are few adjustments you can make to resolve this issue.
It's a common issue caused by web programmers who don't really understand email, or the best way to handle these sorts of forms.
They want users to be able to just hit "reply" to forms submitted by a users on a site. But when you put the user's name in the "From" header and/or set the SMTP envelope MAIL FROM parameter to that address, then:
1. You break SPF
2. You break DMARC
3. You cannot whitelist (as you see)
4. You may trigger off all sorts of spam filter issues, because they will see the mail (properly) as being "forged".
The very best thing to do is to modify the code that sends the email. Use a single, standard address that's in your control, in the "From" header and the SMTP envelope MAIL FROM setting. Then you can whitelist it. It won't look like it's forged. It can pass SPF/DKIM/DMARC checks.
Then set the sender's email address in a "Reply-To:" header. Any email client will respect that header, and hitting the "reply" button will properly compose an email to the submitter's email address.
If you absolutely cannot do that, we can whitelist a specific IP address of the server sending the emails as well as the email address in the Whitelist by Server/IP section of your dashboard.
A drawback of whitelisting the IP/Server alone is that if you have any compromise of that server, and it starts flooding you with spam, those emails will all come through.