ok, so you cannot determine at this point if you had a good install or not, because if you had placed it in the high side, and it bled through to the low side you would know that you didn't braze a plug in the pipe causing a restriction.
You definitely have a restriction, if you have high side pressure and no low side pressure, you have a restriction. The problem is , where is the restriction. I once remembered and never forgot, when I was an apprentice I did a "hard pipe", forgot to remove the plug in the end of the pipe. Brazed the SOB in and later figured out I had an issue. Like you, I opened up the ports though, let loose the charge. later figured out where my plug was because heating it, broke down the rubber plug enough to create a restriction just enough to frost the line, yes, I did have to cut insulation and reseal, but I knew where my joints were. Getting back to your problem.
attach a temp probe to inlet and outlet of TXV, get your delta T, After that, start looking at the piping and what you may have forgot to do during install.