Leandra,
I will definitely contact the parish clerk; I was trying to exhaust all options before I harangued them, but at this point...
I completely forgot I could search for Wills on OPC. That being said, I've gone through the lists they have for both Tonkin and Tresize/Trezise/Tresise and the only one I found that I can connect to Jane Tonkin dau. of Henry and Jane is one for her brother James - identified by his listing of their sister Johanna Toman in the will as a beneficiary. Jane wouldn't be present as she predeceased him, but it's a link, nonetheless.
I'm digging through the Wills listed on the Parish's site that you linked, so hopefully I can find something there.
Yet another moment where I shake my fist in rage at trees created willy-nilly and families that reused the same forenames over and over and over again, and intermarried so much that the trees have become webs.
Sarah