[Chicory]

Each of which is high on FODMAPS, which are theorized to cause or aggravate IBS.

Can’t win for losing, I tell you.

[ConservativeMind]

You may not be far off from being able to have all fibers. You may just need to limit the amounts to where they start to produce gas, to any extent. NDC stands for NonDigestible Carbohydrate in the following graph, and the numbers are the Tolerable Intake grams per day one can take before noticing gas complications. Note that normally people can have 7.8 grams of FOS or only 5 grams of inulin a day before excess gas is generated.

Abstract and full study available here:
https://pubmed.ncbi.nlm.nih.gov/36041173/

[ConservativeMind]

Here is more specific insight for your condition:

Fibre supplements & IBS
https://www.monashfodmap.com/blog/fibre-supplements-ibs/