I know that the Particle Photon does not support HTTPS because that support is not impemented in the Particle firmware.
But no, this does not mean that your code is free of errors, but since this (and the ones mentioned earlier) is the biggest obstacle for your code there was little point to look any further.
There are two possible libraries to add SSL/TLS support for HTTPS
Wolfssl [version 0.0.2; documenting]
TlsTcpClient library on WebIDE published