Issue with tabbing out of the fraction snippet

[coderSupreme789]

Hi there,
I've copied the fraction snippets from this repository, however I've noticed an issue with the fractional snippet inside of the maths environments. Specifically, I use the mk environment to get the $...$ snippet. Normally, I should be able to tab out of the dollar signs. However, if I use the trigger

$ (1+2+3)/ $

I expect this to expand into

$ \frac{1+2+3}{[cursor here]} [tab here] $ [tab here]

This expands, and I can tab into the first tabstop, but then I can't tab out of the mk snippet. I wanted to check if this was just a mk specific issue, and it isn't exactly. I tried this with my align* environment snippet and it will let me tab out of the fraction and the align environment.

However, the plot thickens. If I decide to do the following

\begin{align*}  % triggered with snippet
  \frac{(1+2)/ }{[tabstop here]}    % frac with the // snippet, and the (1+2)/ expands to \frac{1+2}{[tabstop here]}
\end{align*}

I can no longer tab into the denominator of the fraction!

Please let me know how to resolve this issue.

Snippets

Here are all of the relevant snippets, which was determined by modifying snippets with text to make sure that they were triggered.

Fraction generation

local generate_fraction = function(_, snip)
  local stripped = snip.captures[1]
  local depth = 0
  local j = #stripped
  while true do
    local c = stripped:sub(j, j)
    if c == "(" then
      depth = depth + 1
    elseif c == ")" then
      depth = depth - 1
    end
    if depth == 0 then
      break
    end
    j = j - 1
  end
  return sn(
    nil,
    fmta(
      [[
        <>\frac{<>}{<>}
        ]],
      { t(stripped:sub(1, j - 1)), t(stripped:sub(j + 1, -2)), i(1) }
    )
  )
end

Note that I have tried many things including adding another i(2) node after the fraction so that it can tab out, but it makes no difference to any of the cases described above.

Fraction trigger

s({
    trig = "(^.*\\))/",
    name = "fraction",
    dscr = "auto fraction 2",
    trigEngine = "ecma",
    snippetType = "autosnippet",
  }, { d(1, generate_fraction) }, { condition = tex.in_math, show_condition = tex.in_math }),

Maths mk snippet

I've also tried to add i(0) snippet, but it doesn't make any difference either.

s({ trig = "mk", snippetType = "autosnippet" }, {
    t("$"),
    i(1),
    t("$"),
  }, {
    callbacks = {
      [-1] = {
        [events.leave] = function()
          vim.cmd([[
            autocmd InsertCharPre <buffer> ++once lua _G.if_char_insert_space()
          ]])
        end,
      },
    },
  }),

Maths Align Snippet algn

s(
    { trig = "algn", snippetType = "autosnippet" },
    fmt(
      [[
\begin{align*}
  <>
\end{align*}
<>]],
      { i(1), i(0) },
      { delimiters = "<>" }
    )
  ),

Environment

Latest versions of NeoVim, LazyVim, LuaSnip
No issues with other snippets. I will admit that I don't have the package directly installed, but I have copied almost all of the snippets, and the ones copied are exact.
Let me know if anything else will contribute to this / any more details or snippets that are necessary. I am not sure that it's an issue with nested snippets, as I have been able to run multiple snippets inside of each other and tab out of each successfully, in more "stable" snippets.

Thanks.