IPsec can't reach endpoints behind firewall

[prm]

Hello All!
I have four Netgate 2100's that I need to connect with IPsec for constant communication.
Had no issue to make them communicate with each other and can access all four firewalls by connecting to one of them but.... when I try to access switch using IP address behind one of the firewalls - I can't. It states that connection is timed out, whereas when I'm connecting to the same switch through the firewall it connected to - have no issue. I ran packet capture on remote firewall switch connected to and these are results:

Any help highly appreciated.
Thank you,
Stan