Batch IF-Else commands in multi-layer nesting

Question

I just started learning batch, and figured the best way to learn would be to give myself a project. I'm attempting a text-based RPG, and am hung up in one spot. I am trying to nest multiple IF-IF NOT DEFINED, and IF-ELSE "questions" in one "conversation".

if "%choice18%"=="talk hag" (
 if "%glove%"=="0" (
  if "%ketchup%"=="2" (
   echo.
   echo "AHH! Can it really be ye, Cramforth?" the hag asks. "If it be, then ye wouldn't mind answering a few personal questions bout us to prove it, would ye?" GULP! Art thou ready to answer the hag's personnal questions?
   echo.
   pause
   :hag
   echo.
   echo Yes or no:
   set /p choice19=
   echo.
   if "%choice19%"=="no" (
    cls
    echo.
    echo "Then I'll never know for sure," sniffs the hag. You Dungeonheartbreaker.
    echo.
    pause
    cls
    goto West2a
   )
   if "%choice19%"=="yes" (
    cls
    echo.
    echo "Very well. If ye answers questions three, then I'll know thou art me precious Cramforth."
    echo.
    pause
    cls
    echo Where didst we geaux on our honeymoon? A: Wensleydire, B: Rottenscab, C: Blood Area, or D: Zork?
    echo.
    set /p choice20=
    echo.
    if "%choice20%"=="b" (
     cls
     echo.
     echo What did ye get me for me 114th birthday? A: Toad, B: Eyeball, C: N64 Paddle, D: Commemorative mug?
     echo.
     set /p choice21=
     echo.
     if "%choice21%"=="d" (
      cls
      echo.
      echo How many hags didst we have together? 1, 2, 3, or 4?
      echo.
      set /p choice22=
      echo.
      if "%choice22%"=="3" (
       cls
       echo.
       echo "Cramforth! Tis really ye!" mistaking thee for her dead husband. Ye suffer several prickly kisses from the hag which leave the odor of rat liquer on thy face. "No wonder ye died of a bloody head, ye forgot thy FLASK GETTING GLOVE before ye set out to vanquish that rogue dungeon."
       echo.
       pause
       echo.
       echo "Perhaps ye can still defeat that dungeon, even in thy new hotter, spectal form." Um, eww. "Here!" she says and hands ye a wicked FLASK GETTING GLOVE!
       echo.
       pause
       set glove=1
       goto West2a
      ) else (
       cls
       echo.
       echo "IMPOSTER!!" screams Hagatha Christie and leaps at you with jagged claws. At first, ye thinks she's just pouring ketchup all o'er ye. But then ye're like, oh right, that's my blood. Thou art dead. Next time maybe use the NOTES section we provided at the back of the manual.
       echo.
       pause
       cls
       goto HD
      )
     ) else (
      cls
      echo.
      echo "IMPOSTER!!" screams Hagatha Christie and leaps at you with jagged claws. At first, ye thinks she's just pouring ketchup all o'er ye. But then ye're like, oh right, that's my blood. Thou art dead. Next time maybe use the NOTES section we provided at the back of the manual.
      echo.
      pause
      cls
      goto HD
     )
    ) else (
     cls
     echo.
     echo "IMPOSTER!!" screams Hagatha Christie and leaps at you with jagged claws. At first, ye thinks she's just pouring ketchup all o'er ye. But then ye're like, oh right, that's my blood. Thou art dead. Next time maybe use the NOTES section we provided at the back of the manual.
     echo.
     pause
     cls
     goto HD
    )
   )
   if not defined "%choice19%" (
    cls
    echo.
    echo Just answer the hag 'yes' or 'no'. Please?
    echo.
    goto hag
   )
  ) else (
   echo.
   echo "Away with ye," she shrieks, "I speaketh only to me dead husband who died of a bloody head!" She becomes abruptly silent and goes back to her landbeforetimeing. A bloody head, eh?
   echo.
   pause
   cls
   goto West2a
  )
 ) else (
  echo.
  echo "Ye go show that dungeon who's lord, Cramforth! You da lord!"
  echo.
  pause
  cls
  goto West2a
 )
)

The problem I am running into, is that the first user input variable set /p choice19= ignores the IF commands the first time around.

Example:

:hag
echo.
echo Yes or no:
set /p choice19=

User inputs: yes

Ignores: if "%choice19%"=="yes" (

Goes to: if not defined "%choice19%" ( cls echo. echo Just answer the hag 'yes' or 'no'. Please? echo. goto hag

Redirects back to:

:hag
echo.
echo Yes or no:
set /p choice19=

User again inputs: yes

And this time it follows the correct command continuing down the "yes" branch.

However, this poses a problem for outcomes that do not redirect back to the question (ie. if "%choice20%"=="b" () and end the game.

I reviewed a similar issue (Nested IF ( IF ( ... ) ELSE( .. ) ) statement in batch) however, I'm noticing that it is slightly different than my case, being that my variables are defined. So, I'm at a loss. Any ideas?

Note: I am aware that I could restructure the commands without deep nesting to solve the problem, and just GOTO to different :LABELS. I just want to see what's causing this issue.