You seem to be confusing problem formulation with the problem solution. It is true there is a standard way to exchange the problem formulation through something like MPS (though it seems AML's like AMPL etc. have taken over). All this format gives you is a standard mathematical formulation of the problem.
However, the solution is something very specific to the individual solver and they have their own data structures, algorithms and heuristic techniques to solve the problem. None of these are interchangeable or public (by design) and you cannot just insert some outside numbers in the middle of the solver process without being part of the solver code and having knowledge of the entire process.
All these solvers use branch and bound to explore the solution space and "fathom" (i.e. eliminate candidate search trees if the lowest possible value for the tree is above an already found solution). The upper bound that the solver calculates via pre-solve heuristics and other techniques does vary from solver to solver. However, they all have a place for "Upper bound", and there are mechanisms in all of these solvers for updating that value in a current solve.
If this paper were a complementally orthogonal implementation from everything that exists in these solvers today, if it can produce a new upper bound, faster than other techniques, it should be fairly plug and play.
I have an undergrad OR degree, and I have been a practitioner for 18 years in LP/MIP problems. So I understand the current capacities of these solvers, and have familiarity with these problems. However, I and am out of my depth trying to understand the specifics of this paper, and would love to be corrected where I am missing something.
The math programming languages of AMPL, AIMMS, GAMS...etc are dying in my industry and being replaced by general industry languages like Python/Java + Solver API.
However, the solution is something very specific to the individual solver and they have their own data structures, algorithms and heuristic techniques to solve the problem. None of these are interchangeable or public (by design) and you cannot just insert some outside numbers in the middle of the solver process without being part of the solver code and having knowledge of the entire process.