I assume the OP is talking about a TR for endowment. It becomes unusual if it is discussing a TR to do baptisms.
Assuming that it is talking about the former...
The above expresses what I think is the most important point in the entire discussion. The easiest way to get a Temple Recommend at a young age is normally due to some commitment made in regards to the church or personal life. Such commitments, as mentioned, would be things like serving a Mission or getting sealed for all eternity in the Temple (for which one would need a Temple recommend).
No mention of such a decision was noted by the OP. I understand that the Bishop has agreed to talk to the SP, but as the Bishop also noted, the chances for the SP to extend a TR currently is low. Part of this is perhaps the SP needs to see some sort of serious commitment that shows why the individual either needs the Temple Recommend at this time (such as marriage or protections it may afford to a missionary) or the steadfastness that one will need towards the church and it's foundations.
I would suggest patience. In some ways, it is like Marriage. There are those who want to be married for eternity right now so they can fulfill the goal and commandment for it. However, they may not have the right person (or be willing to be married to any person just to fulfill it, or maybe they have no person at all there). If they practice righteousness, pray and listen to the spirit, have faith and patience, all blessings that they strive for in righteousness will eventually be granted to them.
We can all receive personal revelation (and in fact, in instances of marriage I would HIGHLY suggest it), but in all things there is a time and a place. Sometimes it may seem things don't go as quickly as we want them to (and at other times they go too quickly). The desire to have a Temple Recommend is a righteous desire and I hope you keep that desire. If you can, utilize the Temple Recommend that you already have (hopefully) fully and participate in the Temple by regularly going to do Baptisms for the Dead. This can also be an indicator of how dedicated you are to participating in the Temple and how strong your desire for a recommend to take out your endowment is.