Yes - you are tripling the load on a free service that other people rely on.
Web hooks are OK - no continuous connection required. But the TTN MQTT broker can only do so much.
The much preferred design is for a web hook to your master and then you distribute the data to your other servers. MQTT if you have to. But not multiple clients - this sort of usage has been the direct cause of previous server difficulties.
Alternatively, talk to @rish1 about a commercial instance. I’ve not tried multiple MQTT clients on a TTI instance as, well, it’s a questionable design choice.