[c-nsp] Traceroute not working as expected

[james list]

Dear expert
I ve the following strange issue.

In the same broadcast domain (10.1.0.0/24) I have four devices:

1) carrier router .1
2) firewallA .2
3) firewallB .3
4) firewallC .4

Carrier router has a default route to .2 (firewall A).

2-3-4) has gateway to .1

If I made traceroute to a wan location 10.2.0.1 from 3) I get:
10.1.0.1
then wan mpls

If I made traceroute to a wan location 10.2.0.1 from 4) I get:
10.1.0.2
10.1.0.1
Then wan carrier mpls

What can cause the issue only to firewallC?
This is why I guess I cannot establish ipsec vpn from remote to firewallC.

Thanks in advance
Cheers