Change wording in Bubble invitation email

Right now, many of our customers are complaining that when they invite external guests to join a Bubble these external guests have been reluctant/struggling to join the call as they don't understand what the 'join' button refers to (see below).

To them, they think that it means 'Join Rainbow', which they don't necessarily want to do. Therefore, they have suggested the following two remedies:

• Change the content in the call to action too; 'Join Meeting' 
• That way people know that they are joining the meeting, not Rainbow 
• [Preferred Option]: Add some dial-in numbers for the Bubble, similar to when you schedule a meeting
• One thing the customer has noticed is that many of the external guests they invite would rather dial-in to a conference rather than join via the above means. 

Thanks!