Not just to have the lunar module, but to have the explosion occur just when it did. Had it occurred in lunar orbit, even prior to landing, you know what would have happened. But if it had occurred much earlier in the mission (but post TLI) then it might also have turned out badly. The LM might not have had enough consumables for the return trip. I'm pretty sure that after TLI, the only way to do a direct (non-circumlunar) abort is to dump the LM and do a full burn of the SPS, and that was out of the question.
It's easy to forget just how reactive ordinary oxygen really is, especially when pure and under high pressure. I tend to think of fluorine as the most viciously reactive nonmetallic element, and I guess it is; it will cause many materials to ignite spontaneously, while oxygen with those same materials will not. But pressurized oxygen had the ability to displace at least part of the fluorine from the carbon in the Teflon insulation of the Apollo 13 O2 tank.
A Google search found the book "Flammability and Sensitivity of Materials in Oxygen-Enriched Atmospheres", which says that the combustion products of Teflon are primarily CO2 and COF2 - the latter being a phosgene (WW1 war gas) analog about 10x as toxic as CO. An even nastier material produced by Teflon pyrolosis (thermal breakdown) is perfluoroisobutylene, itself about 10x as toxic as phosgene. I wonder, if the Apollo 13 O2 tank #2 had not ruptured during the internal fire, would the astronauts have gotten sick from these Teflon combustion and pyrolosis products?