Thank you for your long time support!
Yes, you can use DVRs with multi-cameras. The thing to keep in mind when looking at DVRs is to make sure the manufacturer lists the RTSP address to each camera in their manual or online information about the DVR. Many do not support RTSP and are proprietary only.
The RTSP address looks like: rtsp://ip-address/camera/1/channel/0.sdp
or something similar that starts with rtsp://
If you can find that, please post here or send me the RTSP address to your DVR for each channel so I can confirm or get it added to MobiLinc for you. You can send to: email@example.com