I would suggest don't quote me on this as the phrase you seek. The literal meaning of course, is to ask that responsibility for a statement not be ascribed to the person making it, such as an insider leaking private information to a journalist. It is a request that the statement be paraphrased, perhaps, but particularly that the name of the person making it not be indicated.
From there, don't quote me has taken on a sense of I believe what I am saying is true, but I may be inaccurate in particular details or I am presenting gossip or conjecture as truth, but I do not have factual information to support it, and from there it has perhaps become an even more generic mechanism for distancing a speaker from the statement. It is often used jokingly in this way, to make a humorous impression, draw an outrageous analogy, make an insulting comment, and so on but quickly indicate to the reader or listener that the speaker is not making a serious argument.
Literal sense of "please do not ascribe a quote to me":
"Holy shit!" exclaimed one Republican on the Armed Services Committee when a reporter shared the news about Mattis. "Don’t quote me on that." (The Hill)
Sense of I am making a statement but understand my information is incomplete or inaccurate:
The West Virginia/Syracuse line had a lot of movement around gametime, so don't quote me on who ended up being the favorite in that game, but I'm fairly certain either every single or almost every single Big 12 team was an underdog for their bowl game. (Dallas Morning News)
Examples of facetious usage:
Roughly speaking, there are 1,000,000 yoga teachers in London alone and only 100,000 studios (don't quote me on those statistics). (The Daily Telegraph)
We in the West scoff our Pop Tarts (surely descended from the Cornish pasty? Don’t quote me on that!)… (The Independent)