TTIG and node normally do not need to be in the same room.
What is "larger distance’?
“Transmission was fine” what is the transmitter here, node or gateway?
“1/4 wave antenna I’m using” I assume you mean the antenna of the node here.
A 1/4 wave antenna is in fact one half of a dipole. The other half is the ground plane. The hat PCB will probably be designed to serve as the ground plane but can be affected by large metal objects. There could also be something wrong with the hat (PCB} itself.
The best would be to also test the TTIG with a different node and test the node with a different (nearby) gateway.
You can check gateway traffic in the console for RSSI and SNR values of uplink messages received by the gateway.
Depending on source and quality, the antenna might be OK but it also may not be designed for the frequency you are using it for (but was sold like that) and some Chinese antenna’s are just garbage.