The reason you're seeing this is because the way Checkpoint create site-2-site tunnels is that they do not ONLY include the encryption "domain" A.K.A the Subnet you define, no the Gateway external interface/public ip/wan side is also included into that.
So what happens is that when your Laptop tries to connect its trying to connect to the "wan" ip of the remote datacenter Gateway, which sees that youre trying to send Vpn traffic from a network which belongs to a Site-2-site tunnel your datacenter gateway has with the gateway on the site that your laptop is sitting behind(though in another subnet not part of the encryption domain)
you need to manually "remove" .
I've been struggling with seeing what the purpose is here for checkpoint doing that, and not even give the slightest hint on what's actually going on if your check logs etc... let alone create an easy way "out" so you're actually able to send traffic to the "remote interface" and not having it forced into the vpn tunnel.