while I suppose you could use it, your not going to get the same flavor. And if your that short on the meat your just going to get less. As long as your mentally prepared for a dish that won't have as much depth of flavor, go for it. If it's what you have , it's what you have.
I'd be tempted not to use it in borscht. Unless you want to add heaps of beef boullion cubes, but even so it wont taste the same. I would be tempted to do a pork and bean soup (your choice of bean, maybe red kidney, bortolloti, chick peas).
A waste of meat otherwise - not being mean but it just won't suit a borscht. Maybe a sauerkraut dish with the pork slow cooked then added inside. Hope this helps somewhat.