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Yes lmoore solved it, manually modifying the program to force a proper destination mac address allows the traffic to route through Opnsense correctly.

I'm fairly new to networking so troubleshooting this has been one massive learning experience.  I appreciate the help, it would have taken me forever figuring out it was being auto dropped due to the layer 2 broadcast address.  Thanks again.  I'm new to the forums here should I mark this thread as solved?

I have 2 devices that need to establish communication between eachother.  each device is on its own network, but connected to the same router.  These are separate physical connections, no VLANs are involved.  The machine is a intel N305 router with 6 2.5gb ports using the intel i226-v chipset.  The machine is running proxmox with 5 of the 6 ports directly passed through to opnsense.  Both devices are on ports directly passed through to opnsense.

Device 1 is on network 10.0.0.0/24, Device 2 is on 192.168.4.0/24.  Both machines have been given static IP's via KeaDHCP.
Machine 1 is set to ip 10.0.0.55, machine 2 is assigned ip 192.168.4.27

Machine 1 is a server that handles file sharing, Machine 2 is a system that requests the files.  Communication occurs over 2 ports.  Port 62966 and 62967.  Machine 2 broadcasts a multicast request over port 62966 that hits the router and runs through UDP-Broadcast-Relay which makes its way to machine 1.  machine one than responds to machine 2 letting it know its IP and the port to use for data transfer.  Everything works as it should both machines see each other just fine and all communication passes normally.  the problem is when machine 2 sends a UDP packet requesting data from machine 1.  That packet hits the router interface but doesn't seem to go anywhere beyond that.  I've enabled firewall logging for everything including NAT rules under the advances settings. I don't have captive portal, or ipsec enabled.
I've attached packet captures that were run directly inside opnsense.  The packet in question is under interface 2 and it repeats 4 times.

I'm trying to pass a very specific UDP packet from one interface to another on different networks on the same router.  I've run a packet capture on both interfaces, I can see the packet coming in on the input interface but it just disappears after that.  There are no firewall logs indicating the packet was blocked.  I've tried sending the packet through with the firewall and NAT disabled but it still doesn't get processed.  I'm convinced its either the interface or Kernel blocking the packet before the firewall can process it.

If anyone has any tips on where I can look to see why the packet is being blocked that would be great.  Any help would be appreciated here as I'm at a complete loss on where to troubleshoot next.