Thank you for your post.
It does not sound that there was any actual penetration as the condom broke as he was trying to insert his penis, and obviously there was no ejaculation inside either. Therefore that would not require PEP.
However if there was penetration and the condom broke whilst inside, there would be a possible risk as precum could infect, even though I would still think that under these circumstances the risk to you would still be low as it was brief (risk up to 3% maximum). Assuming that he was positive and this last scenario is what actually happened, PEP could be considered. PEP needs to be started as soon as possible, within 72 hours of the possible exposure. You could do so in order not to waste time, but see if you could get this man tested in the meantime; if his test is negative, you could then stop PEP.
All depends on the actual circumstances as described above.