I think there is one receptionist that answers the calls for both companies.
If this is the case I would set it up as follows.
BCM
I would create a hunt group (624)
Set the huntgroup as broadcast
Set the busy/overflow parameter to queue
Set the queue timer 15,30,45 or how ever long you want the reception phone to ring before the call goes to voicemail.
Set the overflow dn as the voicmail extension (451)
Add the reception DN to the huntgroup as appear and ring.
Add the target line for company A
Then create a hunt group exactly as above except add the target line for company B
This way you will see the call for each group appear at each key helping reception to identify what number has been rang. This will help to answer the call with the correct company name.
Call pilot
Create 2 mailboxes on the call pilot for hunt group 1 and hunt group 2 set the alternative ext parameter to be the reception DN, Set the extension DN as the hunt group.If you need the reception to be notified for both hunt groups. This will be a problem because the extension can only be set up with message notification on one mailbox. The thing I normally do is set the remote notification under the mailbox to ring the reception extension to ring when the hunt groups receive a message.
BCM
The boss setup I would use answer DNS to notify the reception phone when the bosses extension is being rang internally and externally.
I hope this makes sense
Marshall