TRX broadcasttransaction 401 error

We are attempting to switch from trongrid to quicknode for TRX http node service. All of the methods that we have tested, except broadcasttransaction seem to work.
401 unauthorized is returned every time we attempt to broadcast the signed transaction (see the screenshot below).
The same code works fine with trongrid.
Whitelisting our IP did not help.
Please also see the code snippet (we use tronpy library)


Kindly open a support ticket with our internal team here so we can better assist here.