2-Pair Ethernet Cable works only on one specific router

I have an IP video doorbell that coects using a 2-pair telephone line. I have managed to coect it to my DSL router (Linksys WAG320N) successfully and coection is working fine with live streaming over inteet.

Now, due to limited upload speed of my DSL router (only 512 Kbps) where I need a minimum of 1 Mbps upload line, I used a 4G Router but when I coect the same 2-pair line to the router (HUAWEI LTE CPE B593) it does not fire and the led light does not blink. Actually the Etheet port status shows as discoected. So, I tried coecting the line to a switch then to the DSL router, but again it does not coect and shows as discoected. I tried different setups and the only thing that works is coecting direct to the DSL router! So all other routers/switches could not coect to this etheet line.

So what I can conclude is that this is a hardware issue but not sure exactly why is that and how to enable the switch/4G router to be able to coect to the doorbell through this 2-pair Etheet line (please note I used a 10/100 MB switch to eliminate Gigabit compatibility issues but still line will not fire)

Any ideas how to make this 2-pair cable coect to other routers/switches? is this related to some configuration in the router? or this is hardware compatibility with new routers/switches? would appreciate any suggestions ..