I am not aware of any Arab countries not continuing their diplomatic presence after the fall of the Al-Assad regime.
The only Arab regimes that seem somewhat disappointed that Al-Assad fell is Iraq (but not really when you think of it as the Iraqi government prevented PMUF deployments to Syria, main Iraqi Shia clerics, Al-Sadr and others, hailed the Al-Assad removal and called it an internal Syrian affair), UAE (mainly due to them investing in trying to align Al-Assad away from the Iran-Axis - seems to have been partially successful given the leaked documents) and my gut feeling the Al-Sisi regime. The latter because it is a military regime as well (Egypt is run by the Egyptian military since the 1952 coup) so naturally he feels threatened given the recent history of the MB (Morsi) in Egypt.
However the new Syrian rulers have no such ambitions and have already had meetings with officials from KSA, Egypt, Jordan, UAE, Qatar etc.
Everything will take its due course in a natural way.
I think that what brother
@mulj posted earlier of the future Syrian prospects was very encouraging and promising.