Sonicwall Nightmare

Hello to all reading! thank you for taking a bit of your time to read this. please forgive any mistakes i make or grammar errors. i am a new IT and i was given the task to tackle a new project. (Sonicwall Skills: Rookie/Novice)

Problem is as follows:

BACKGROUND: There are currently 2 offices 2 sonicwalls Model TZ210 and TZ 215 (with updated firmwares). Both offices have an active VPN connection with NetBios and current tunnel speed is (@350kb & 450kb). B office uses this tunnel to print to A offices warehouse printer, and also utilize this vpn to connect to an accounting software that A office uses im guessing it's for payroll. B office upper management decided they wanted to use our ISP (ATT business class fiber @50Mbps Down & Up). For this task i was approved the equipment and project for a PTP connection with Ubiquiti equipment. Equipment was setup professionally by the use of third party local company.

PROBLEM: i have now set up the PTP to send internet from A office to B office succesfully! test speed is 47Mbps @B office which is also what we have here in A office, (the PTP equipment is very expensive and top of the line). Now that the PTP connection is up and running i would like to remove the VPN since i know the PTP connection is more faster and better. the VPN at this point however is still active, but routed by the 2nd isp we have in both office locations. How can i make/Configure Office B firewall to ping and see equipment from A office? i only have internet from A office but cannot see anything from A office. this problem is causing me to keep the vpn alive since they need to print and need to use the accounting program they have in B office.

CONCLUSION: i have done this setup before by off the shelf routers which is as follows i don't know what to name it but its the following ( A router receives internet, so on B router on the wan port i put a lan IP address from the dhcp pool of A router and its that simple, now B router by protocols of TCPIP can now still see equipment from A dhcp pool and can communicate by either SMB, PING, or any other form of configuration) How can i implement this situation in these Sonicwalls? i hope my post made sense and thank you so much for reading.