Do you mean in the code he provided for P2SH version?
It's just for the generation of P2SH address which is not used to spend the transaction, he did that to conveniently create an output with that script.
The Redeem Script is already the "
dumb_script=7551".
This is literally the instruction to spend it:
Comments: Used "OP_1, OP_DROP, OP_1" as the sigScript, which, including length prefixes, is 0x0451027551 - all it took.
He used "
OP_1" to fulfill the RedeemScript "
OP_DROP, OP_1"
I tried the redeem script on cointools(the link he provided) and it did not work I even tried on Coinbin and still it didn't work.
I might be getting something wrong or they stopped supporting non standard scripts.