Trying to set caret in rich-text-block with range.commonAncestorContainer to get deepest text node for inline elements. Is this possible?

Question

I know cursor questions have been asked to death so bear with me. I haven't found a solution that works for caret position in inline style elements when there are multiple text nodes e.g. normal text bold sentence normal text.

If I getCaret position, update the block content, setCaret position it will work if the entire block is bold or italic etc. I've been doing that using treewalker.

I can use range.commonAncestorContainer to get the deepest node in the getCaret selection, however, applying that node as my range.setStart(node, offset) in my setCaret function errors as selection 1 is not of type node. Is there a way to retain the node being a valid node from one function to another for this? Thanks for your help.

 const handleContentChange = (e) => {
    const caretAt = getCaret();
    function getCaret() {
      let sel = window.getSelection()
      let range = document.createRange()
      let node = range.commonAncestorContainer
      console.log(range)
      let offset = sel.anchorOffset

      return {node, offset}
    }
          
    const sanitizedInput = DOMPurify.sanitize(e.target.innerHTML);
    onContentChange(sanitizedInput);
    setTimeout(() => {
      setCaret(caretAt);
      }, 0);
  
      function setCaret(caretAt) {
        let sel = window.getSelection();
        if (!sel.rangeCount) return;
    
        let range = document.createRange();
        range.setStart(caretAt.node, caretAt.anchorOffset)
        let node = el.childNodes[0];
        let offset = caretAtRef.current;
    
        // If the first child is an element, find the appropriate text node
    
        range.collapse(true);
        sel.removeAllRanges();
        sel.addRange(range);
      }
     }

I've tried iterating through treewalker filtered text nodes and doing a cloned range, getting caret position, applying to new range.