I'm trying to do a Charisma (Persuasion) check with no DC to compare it to!

Encounter with a Hollyfant

I'm playing the DnD solo adventure "To Hell and Back Again" and there's no DC to compare my check Charisma (Persuasion) to. Here's the passage:

Hi there! I’m Lulu, and I’m a hollyphant! At least I think I am. A devil with six tongues told me so the other day, right before he tried to eat me,” the small elephant-like being blurts out, and then continues, not slowing down until it runs out of breath. “Wow, I’ve never seen anyone make it out of that cave alive. You must be really special, huh? So tell me, my new bestest special-friend, how did you get out of there? And what’s it like inside that creepy cave anyhow? I think I went in there once, but I can’t remember anymore. I can’t remember lotsa things.” Lulu’s head falls a bit at her admission, and she blows a small, sad puff of sparkles out of her trunk. If you tell Lulu the truth about how you got here, go to B17. If you lie about how you got here, make a Charisma (Deception) check. Note the result and go to B18. If you try to cheer Lulu up, make a Charisma (Persuasion) check. Note the result and go to B19. If you respond cruelly to Lulu, go to B20.

• This is very similar to your previous question about checks with no DC. Jul 25, 2022 at 0:13
• I would suggest if you find another similar situation you read ahead and around in order to try and find it, there should always be a DC Jul 25, 2022 at 5:12

The DC for the check is in the next paragraph the adventure is directing you to go

Look at the wording:

If you try to cheer Lulu up, make a Charisma (Persuasion) check. Note the result and go to B19.

It is telling you to roll the check, write down (or memorise) the result and go to passage B19 to see whether you passed or failed. The passage then starts with giving you a DC and splitting into 2 paths again depending on what you rolled.

You don't know the DC, yet

The piece here are the lines:

Note the result and go to X

They tell you to make the check, roll the d20, add your Charisma modifier and proficiency bonus if proficient, and then remember that result. The section you go will make use of that number (ie. tell you the DC or otherwise give you a success or failure or other outcome based on the roll).

Arguably, this is kinda closer to how normal (with a DM) checks work, where you make a roll and tell them the result without ever knowing the DC.