Messages from teams or groups are sent to profile contact info rather than account contact info. Even if you have your email address and phone number connected to your account under Account Settings, you will still need to make sure this contact info is correct in the player's profile, found under Household.
No, you will only be able to connect one phone number per profile.
Yes, just add the second person's email address under the player's profile, found under Household.
If you did not receive an activation or password reset email from SportsEngine after 10 minutes, be sure to check your spam or junk folder in case the email was accidentally flagged as spam.