Why not every [x,y] coordinate on the Secp256k1 curve corresponds to a valid uncompressed publicKey?
Both are valid public keys just that in the first case the uncompressed public key is not represented in a valid hexadecimal format. If you look closely, your Qy has 63 hexadecimal digits (so there is a 'half-byte'). Although hashing can be done in bit boundaries, most standard implementations out there do not support it.  Just try to concatenate '0' at the start of the Qy to get Qy = 0691AA44502212591132AA6F27582B78F9976998DE355C4EE5960DB05AC0A2A3 so that you get a full byte. So now your uncompressed public key is 04B8F0170E293FCC9291BEE2665E9CA9B25D3B11810ED68D9EA0CB440D7064E4DA0691AA44502212591132AA6F27582B78F9976998DE355C4EE5960DB05AC0A2A3, which would hash to P2PKH address: 17Y1XJiC72f2kyJnzwBdkaPQEGgaD1aroR