Requests
 

Buenas tardes:

If I want to ask a receptionist to have his/her boss call me, could I say:
Qué me llame, él, por favor
¿Podrías decirle a él llamarme, por favor?

Is there a more colloquial way to convey the same thing?

Thanks

The first is OK, but there's no need for the first comma. This is a direct command. There is no hint of politeness. You could add Dígale as the first word and not change the meaning.

The second sentence is more polite than the first. In it, you should avoid using the second person when addressing someone (unless you customarily treat that person that way). There should be two clauses:
¿Podría decirle (a él) que me llame, por favor? (Use a él as needed for clarity.)
¿Le podría decir (a él) que me llame, por favor?

You can also say: ¿ Podría decirle que me llamara?

Thanks Rusty, as usual very helpful.

BTW, the receptionist I was thinking of is a pretty good friend, hence the use of the familiar tú form.

Really? I had no idea you could use the imperfect subjunctive in this kind of structure.

Thanks María José

This is what I would say, too, but I see that a lot of people don't give weight to the fact that the main clause is in the conditional mood (hence the use of the imperfect subjunctive in the secondary clause). Instead, it seems that they're thinking the initial verb is a 'polite' form and that it doesn't follow the rules.

Would this work?
Si pudieras, decirle que debiera llamarme.

Small correction, but otherwise OK.