Thank you for your inquiry. Now if you are talking about having the same Peplink have both an IPSEC and a Peplink Site-to-Site to different units (1 Peplink to 2 different boxes w/the different VPNs), this should not be a problem.
In regards to your issues creating the IPSEC VPN, let’s have you create a support ticket and we can dig further into the issues at hand at the following link-