If one misses to daven Mincha not because he forgot or was in an accidental situation, but he just happened to be in an important business meeting were a large capital was involved, can he still daven Maariv twice?

Shulchan Aruch (O.H. 108: 1) rules that one who forgot to daven one of the Tefilos, should daven twice the next one to complete the missing Tefila. However, he rules that the above applies only when it was done by unintentionally forgetting or any other situation out of one’s control. Shulchan Aruch (ibid 8) also includes the one who was engaged in his monetary business and could not stop since that would create a loss. However avoiding making money is not included. Horav Shlomo Miller’s Shlit’a opinion is that even in the most important of business meetings, one could ask to be excused to go and do his necessities and have the time to daven. Therefore, one should not daven Maariv twice. However, as mentioned in hulchan Aruch (ibid 7) one may daven a Tefilas Nedava or a voluntary Tefila, if he can fulfill the required conditions for doing so