RollTwice Rule Element should support resolvable selectors

[JordanRL]

I created a feat that has only two RE's on it: ChoiceSet and RollTwice. Here they are (after having already been put on an actor):

ChoiceSet:

{
  "choices": [
    {
      "label": "PF2E.SkillAcr",
      "value": "acrobatics"
    },
    {
      "label": "PF2E.SkillArc",
      "value": "arcana"
    },
    {
      "label": "PF2E.SkillAth",
      "value": "athletics"
    },
    {
      "label": "PF2E.SkillCra",
      "value": "crafting"
    },
    {
      "label": "PF2E.SkillDec",
      "value": "deception"
    },
    {
      "label": "PF2E.SkillDip",
      "value": "diplomacy"
    },
    {
      "label": "PF2E.SkillItm",
      "value": "intimidation"
    },
    {
      "label": "PF2E.SkillMed",
      "value": "medicine"
    },
    {
      "label": "PF2E.SkillNat",
      "value": "nature"
    },
    {
      "label": "PF2E.SkillOcc",
      "value": "occultism"
    },
    {
      "label": "PF2E.SkillPrf",
      "value": "performance"
    },
    {
      "label": "PF2E.SkillRel",
      "value": "religion"
    },
    {
      "label": "PF2E.SkillSoc",
      "value": "society"
    },
    {
      "label": "PF2E.SkillSte",
      "value": "stealth"
    },
    {
      "label": "PF2E.SkillSur",
      "value": "survival"
    },
    {
      "label": "PF2E.SkillThi",
      "value": "thievery"
    },
    {
      "label": "PF2E.SkillLore",
      "value": "lore"
    }
  ],
  "flag": "trulySkilled",
  "key": "ChoiceSet",
  "prompt": "PF2E.SpecificRule.Prompt.Skill",
  "selection": "deception"
}

RollTwice:

{
  "key": "RollTwice",
  "selector": "{item|flags.pf2e.rulesSelections.trulySkilled}",
  "keep": "higher"
}

The RollTwice option does not work. However, using the following RollTwice instead, we see that it works:

{
  "key": "RollTwice",
  "selector": "deception",
  "keep": "higher"
}

There is some kind of flag resolution bug that affects RollTwice that does not appear to affect many or any other RE's.