While every university is different, the following answer assumes common sense:
Whether an article is on ResearchGate or indexed by Google does not provide meaningful evidence that you have published an article.
When is a publication available online? An article is considered to be available online when it is available from the publisher's website. The delay between acceptance and online publication varies between journals. Some journal will put an accepted unproofed version of the manuscript up almost immediately. Other journals wait until proofs have been completed. This is often a few weeks after acceptance. Other journals have no "online first" version and you have to wait until the manuscript has been allocated to an issue, which can take anywhere from months to even a year or more.
For this reason, when evaluating a researcher or a PhD student, it often makes more sense to count publications once they have been accepted. This is especially true for PhD students. Now, for journals that make articles available online rapidly (e.g., less than a month after acceptance) then the difference between acceptance and online is minimal. However, where there is a major time lag, then it would be a stupid policy for a university to require a PhD student to have the publication actually published, as opposed to being accepted.
So in summary:
- If you've published your articles in a journal with a short lag between acceptance and online access, then you might just want to wait a few weeks.
- If you've published your articles in a journal with a long lag, then you should talk to your university about providing other evidence of proof of manuscript acceptance (e.g., editor acceptance letters).