Unable to use script path using buidl python lib.

I’ve been trying to figure out how to use a specific script path using the buidl python lib. Currently I’m assuming there’s a problem with how I construct the p2tr address, or a bug in how the control block is calculated.

The following errors appear when broadcasting spending transactions: Witness program hash mismatch

My code can be found in the gist or below.

from buidl.hd import HDPrivateKey
from buidl.ecc import PrivateKey
from buidl.taproot import TapLeaf, TapBranch, TapScript
from buidl.script import Script
from buidl.op import *
from buidl.tx import Tx, TxIn, TxOut
from buidl.taproot import ControlBlock
from buidl.witness import Witness
from buidl.script import P2WPKHScriptPubKey, ScriptPubKey, decode_bech32

pvt_key = PrivateKey(12345, network="regtest")
internal_pvtkey = PrivateKey(3333, network="regtest")
internal_pubkey = internal_pvtkey.point

# leaf_a = Script((op_1, op_add, op_2, op_equal))
# leaf_b = Script((op_2, op_add, op_4, op_equal))
# leaf_b = Script((op_1, op_add, op_5, op_equal))
script_a = TapScript((81, 147, 82, 135))
script_b = TapScript((82, 147, 84, 135))
script_c = TapScript((81, 147, 85, 135))

leaf_a = TapLeaf(script_a)
leaf_b = TapLeaf(script_b)
leaf_c = TapLeaf(script_c)

branch_ab = TapBranch(leaf_a, leaf_b)
branch_abc = TapBranch(branch_ab, leaf_c)

address = branch_abc.external_pubkey(internal_pubkey).p2tr_address(network="regtest")
print("Deposit funds to:", address)

# SPEND PATH B
amount = 1_000_000
cb = branch_abc.control_block(internal_pubkey, leaf_b)

tx_in = TxIn(bytes.fromhex("07fdfaf3541c26d5fc18f644f338d8ac4e47f7bcc83c41192741990d150b8d19"), 1)
tx_in.witness.items = (encode_num(2), leaf_b.tap_script.raw_serialize(), cb.serialize())
tx_ins = (tx_in)
tx_outs = (TxOut(998000, P2TRScriptPubKey(decode_bech32("bcrt1py7e8e0q7pdkxwyp2tjn65k4kd5kgch0aqe03jzjczn96xat6nwjswsu892")(2))))
tx = Tx(2, tx_ins, tx_outs, network="regtest", segwit=True)
tx.serialize().hex()
# 02000000000101941ea2c9c9236e92e0d94530d0de3694012f0d3902399dc680294ef2e82a0e780100000000ffffffff01301b0f0000000000160014904946363de1f2cb5ce439e5ed038492051b2785030101045293538841c04cecb33a915e2c3b189eb6ee45fa4eb3eddeff09729945c600f893bd4381b294c95c39c9307263577e8ed45b4d6ad91cf6f47f42476e0e40676b1f028be1360600000000
# I always get: `non-mandatory-script-verify-flag (Witness program hash mismatch)`

Since I was able to successfully generate and use a p2tr address using the bitcointx library (using the same tabscript), why would I assume that this is most likely not the case? build Either the library is written correctly or I’m misunderstanding something.