Question about Baby cam T83211D1

Hi, got a question

I own one Indoor Cam 2K pan an tilt (T8410) , and one Indoor Cam 2K (8401).
If I were to purchase the baby cam T83211D1, can I connect my other two cameras to the display unit of T83211D1?

In description says that the T83211D1 display unit can be connected to 4 cameras. Can I use it with my existing cameras?

Thanx all