Rejecting the digraph method (which is probably the simplest) doesn't have much meaning because they have different sounds in different languages all the time like ch in English and German.
Anyhow, it certainly can be difficult convincing non technical political people. Modifier letters are more legible than modifier punctuation IMO so that maybe an option And the labels on keycaps don't mean anything at all. We in India use the plain QWERTY keyboard all the time for our scripts. In any case, the linguistic committee should present their recommendation along with a new set of actual keycaps and an MSKLC or such input method to just show the president that what is recommended can be input using "a standard keyboard".