the scientists who posit those ideas would disagree with you I think.
That is simply not true. I have been a subscriber to Scientific American for over 40 years, plus I have read about a half-dozen books written by research cosmologists on the BB over the last several years. Both the concepts of quantum mechanics and the hypothetical possibility of infinity are very much in the running and, as a matter of fact, most cosmologists that I've read lean in the direction of both likely being true. However, they are as stuck as we are in that there's not anywhere near enough evidence to conclude that there is a multiverse or that infinity exists.
What is your idea of infinity? Something without limits? What has no limits? something natural? what is natural? what is it?
Anytime there is matter, energy, or sub-atomic particles of any type, there will logically have to be limits because each has its own characteristics, and "characteristics" logically necessitates limits.
I use the term "natural" in this context of my "leaning" as applying to literally everything, ala Spinoza's approach. Matter of fact, he used the name "Nature" as another name for God. Because all things in Nature have characteristics, they therefore have limits.
For those of us Jews who tend to take this approach, most of us do not differentiate between pantheism or panentheism, and neither do I. Essentially it's beyond my job classification. Therefore, I tend to say my position this way: Whatever caused the universe/multiverse I'll call "God" and pretty much leave it at that. If "God" is a conscious deity, so be it. If "God" is merely the energy of creation as Einstein hypothesized, so be it.
Or, to put it another way, whatever is,
is.