black bugs - and - jumping around are probably fungus gnats ...common around wet potting mixes ....they might "go-away" after a total repot into something chunky
this one ...think you are right - stems look like a ficus of some sort
with stem and upper root tied into a knot(s) ....
2nd pic looks like a ficus too ....does look like a graft ....onto what looks, sort of like an adenium caudex ......but the "skin" is all wrong .... adenium caudex were roots at one time, skin should be almost smooth ....without lenticular leaf scars or horizontal lines ....verdict
