I think the answer is Yes and No to the question I asked in my subject heading, because Yes, he should be DQ as he has burnt the Basic Law before, and said he would not mind to burn it again in future if he finds it would be necessary means to protest against any NPCSC decisions. Moreover, he has met the Japanese politician who supports HK, Taiwan, Tibet, XinJang, Inner Mongolia secession from China's sovereignty, and called for all these regions to initiate more radical independence movements. So, legally speaking, Mr. Au Lok Hin should be DQ without any hesitation or mercy even he now has won the seat in the LegCo by-election. Nevertheless, realistically, I don't think he will be DQ ASAP by DoJ, SJ in the court, but rather would wait until NPCSC made another decision & interpretation to ban any LegCo lawmakers & candidates from doing such actions as Au did in the past to join election ever again, only then will DoJ, SJ dare to take action to DQ Au Lok Hin. Thus, I am worried filibustering will only worsen further now, as the over half majority veto vote in GC sector in LegCo has returned to opposition side now, so from now on, HK people will suffer a lot much more painfully than before the by-election. I can only wish NPCSC will make such key decision promptly or else HK will become a dead city!