I can only agree with @Zeeha OP, about just changing clinic.
I don't know the answer about adding the testing on your NHS round. But frankly from what you've said, I wouldn't be all that happy with your clinic either.
PGT is not 100% (no test is), but is' not 'just random' - it tells you how many chromosomes your embryo has. It increases the chances that the embryo chosen is euploid and will result in a live birth and lowers the chances of wasted time and heartache.
You never know, you might get all your embryos tested and realise that they are all aneuploid and would never have worked. That would answer a question, rather than just putting you on further random medications 'just to try something different', despite the fact that you are perfectly healthy as far as they know. Why don't they just try doing a DNA fragmentation test or PGTA? - it's much more likely to be to do with the male side if you are normal as far as you know.
Sorry, I'm feeling a bit frustrated with your clinic on your behalf!
Your consultant is also fobbing you off by saying you'd get similar results from a donor, without even properly testing your husband's sperm or your embryos they can't possibly know that. Donor sperm is generally very good quality and our fertilisation rate with donor sperm was about 10x that with my husbands sperm, and we got 5 embryos to freeze. None of the embryos made from my husband's sperm were good enough quality to freeze.
The NHS really don't like donor use though - another reason we went private is that we sat on a waiting list for over a year for our third round of IVF, only to be told that they wouldn't let us do it with a donor, it had to be my husband's sperm (even though it had been clearly demonstrated that it wasn't good enough).
So we waited a year and were then turned down for NHS funding because we had severe male factor issues and wanted to use a donor.
Honestly - if you've got the money and can do it - I would just go private. You'll save yourself so much heartache and frustration.