From looking again at your recruiting post from last December, unless things have changed, your son is a probably a legit HA D3 catcher recruit who would like to get looks from HA D1 schools, and you're probably right that being a LH hitter might help him get noticed.
If that is correct, trying to become a LH C at this late date seems like a really long shot means to that end. Nothing wrong with that, but I think the odds of him learning a LH swing in a few months that his competitors have taken many years to perfect are really, really long.
That said, if you both feel that this is his best chance of getting those D1 looks, and he will forget about playing baseball if it doesn't work out, sure, why not go for it.
OTOH, if he's going to try to find a good HA D3 slot if this doesn't work out, this may hurt his chances at that slot or at least hurt his chances at PT down the road. Because if he can't get that LH swing down, he will have wasted all that time he could have spend working on his RH swing, working on his defence, getting stronger, etc.