Does "reponn" usually take "bay"? Like "Li poko reponn ban m" rather than "Li poko reponn m"? Can you list some verbs than usually take "bay?" (Also, does the following make sense, "M ka konprann lè moun pale kreyòl si yo pa pale tenkantenk.")

BAY is used after certain H. Creole verbs as if it was the preposition TO.
You'll see it used with the following verbs:

1. Vire do → abandon, turn away, turn one's back.
    Mwen santi Bondye vire do ban mwen.
    I feel that God has turned his back to me.

2. Pote → to bring, to carry
    Pote liv la ba li.
    Bring the book to him.

3. Ouvè → to open
    Tòk Tòk tòk... Ouvè pòt la ban mwen!
    Knock knock... open the door for me!

4.  reponn → to reply, to give an answer
    "Li poko reponn ban'm"
     "He has not yet replied to me."

5. Kriye → to cry
    Pinga w vin kriye ban mwen lè w tonbe nan tchouboum.
    Don't come crying to me when fall into a mess.

 See this link:
Verb BAY acting as a preposition

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Yes, you can say Li poko reponn mwen (with MWEN instead of the contraction "M").  We don't use contractions after a consonnant.
example:
You can say.
Mwen prale avèk li.
but you cannot say
Mwen prale avèk l.

See Contractions after consonants or vowel.

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Tekantenk → equivalent, reciprocal, give and take, measure for measure, eye for eye, teeth for teeth

 "M ka konprann lè moun pale kreyòl si yo pa pale tenkantenk."
tenkantenk, in this sentence, seems to mean word for word, exact match of a word.  Whatever comes after this sentence may determine the meaning precisely.
"I can understand that when someones speanks Creole if they don't speak word for word"

Haitian Creole ↔ English Reference, Look up Haitian Creole and English Words