What is the right way to express a work relationship

I want to convey the idea that the actor worked in Quentin Tarantino's films in his early days --> early days of the actor, not Tarantino.
Which version is correct?

1. He worked in three other films by Quentin Tarantino in his early days. --> This may read like I am talking about Tarantino's early days, not the actor's.
2. He worked in three other films by Quentin Tarantino, in his early days. --> Does using the comma after Tarantino clarify that I am talking about the actor's early days, not QT's?

I understand I can solve this confusion by writing it like this: "In his early days, he worked in three other films by Quentin Tarantino." But, I want to know if there's a grammatical solution in the initial versions of the statements.

thanks

I would recommend your proposed third alternative, punctuated as follows.

In his early days he worked in three other films by Quentin Tarantino.

This is a substantial improvement to the sentence, because the time period (his early days) is immediately adjacent to the verb (worked). As a result, there is no longer any ambiguity.

I do not see any version of your first two alternatives that would avoid ambiguity.

The ambiguity comes from antecedent-matching. Both “He” and “Quentin Tarantino” qualify as the antecedent to “his”. Proximity tends to push first impressions away from your intended “He-his” match.

The comma doesn’t really help resolve the ambiguity. What it does is add emphasis to the timing - they worked together in the early films rather than later ones.

To resolve the ambiguity, you can reword as you suggest, so that “he” is closer to “his”. The alternative is to change the pronoun to something more specific, but this is problematic here because the antecedent is another pronoun.