I realize how you want to read the verses, but it simply says there were “certain Greeks among those who came up to worship at the feast.” It does not say these Greeks were worshipping at the feast, which is you’re reading. (Which would have been inappropriate for uncircumcised Greeks to observe.)
It may simply mean that Greeks traveled with Jews who were coming to worship, and these Greeks sought out Jesus. You are hard pressed to find evidence of Greeks (unless they are proselytes to Judaism) observing these Mosaic codes. Even the proselytes were not permitted to observe certain feast, such as Passover. Besides, it’s not even clear these Greeks were believers in Jesus at this time. They may have just been curious. Note what is written earlier, “Therefore the people, who were with Him when He called Lazarus out of his tomb and raised him from the dead, bore witness. For this reason the people also met Him, because they heard that He had done this sign”
You can not build a very strong case on pure speculation, esp. when all the evidence is against you.
lol. You are certainly stubborn. That's about as clear as it gets. Read commentators. Read history. Read other translations:
(ESV) Now among those who went up to worship at the feast were some Greeks.
(MRC) Now there were certain Greeks out of those who were going up to worship at the festival;
(MSG) There were some Greeks in town who had come up to worship at the Feast.
(WNT) Now some of those who used to come up to worship at the Festival were Greeks.
(ALT) Now [there] were some Greeks from the ones going up so that they should prostrate themselves in worship at the feast.
(EMTV) And there were some Greeks among those coming up, so that they might worship at the feast.
(ESV) Now among those who went up to worship at the feast were some Greeks.
There WERE gentiles who recognized that the Jews worshipped the one, true, God. These gentiles recognized that he wanted people to worship him in the way he specified. Scripture is full of examples of gentiles who recognized this. Nebuchadnezzer comes to mind. It's like you think that Peter, Paul and the rest totally scrapped everything they ever knew, including scripture and the example of Christ, and invented their own rules.