Creating static route a possible solution to joining separate networks?

due to limiting circumstances,

network 1 (192.168.100.0/24): we have a router with only 2 ports on it: 1 for internet and 1 for the switch.

network 2 (172.16.254.0/24): juniper srx 210 and cisco 3560 switch.

network 2 needs to access a specific device on network one. the vendor is going to configure a port on the switch on network 1 for network 2. on the network 2 side, should we just configure a static route on one of the interfaces of the SRX210 to handle network 1? or if the vendor is willing to VLAN should we pursue that solution?

thanks in advance!

Yes, static routes are the easiest method. Otherwise you'll need to create trunks and VLANs or change your gateways to the 3560. You said "one device" so I assume you want to configure firewall rules and the like.