The Arabic root was ruled out for a lack of evidence. Oxford English Dictionary, in Macabre, n.1:
There is no evidence to support the theory that the word derives from Arabic maqābir, plural of maqbara cemetery (Moroccan colloquial Arabic məqāber, plural of məqebra tomb), or from Syriac meqabberēy gravediggers.
The first instance of the word Macabre is in Jean le Fèvre's poem Respit de la Mort. Here is how the word appears in a 14th century manuscript, Francais 994.
Je fis de macabre la dance (close-up on image from Martin Hagstrøm)
(I have done the dance of macabre)
Where does Jean's word Macabre come from? That is difficult to determine. That said, we have some orthographic evidence that it could be based on Maccabee. The Trésor de la Langue Française informatisé (TLFi) has a long entry about Macabre that describes in greater detail both the Arabic and Maccabees hypotheses. (Note: for the full entry one can access the main site, enter, search for "Macabre," and find the entry. For ease of access I also share this link to a screencap of the full entry. Be sure to give TLFi due credit.) I translate with the help of Google Translate:
Orig. controversée (voir FEW, t. 6, 1, pp. 2a-3a). Les étymol. orientales qui ont été proposées (ar. maqbara, maqbura, plur.; «cimetière», v. VAN PRAET cité par CHAMPOLLION-FIGEAC, op. cit., pp. 367-368; syriaque meqabberêy, meqabr ey «fossoyeurs», v. Fr. mod. t. 15, pp. 96-98 et Romania t. 71, pp. 408-412) manquant de fondement, il semble préférable de voir en Macabré (lu à tort macabre au XIXe s., cf. 1811, supra et Romania t. 18, p. 513) une var. du nom propre d'orig. biblique Macchabée (cf. p. ex. ca 1190, GUI DE CAMBRAI, Vengement Alixandre, éd. B. Edwards, p. 96, 1748 [var. 2e moitié XIIIe s.]: Judas Macabrés; ca 1200, 2e Continuation de Perceval, éd. W. Roach, t. 4, p. 500, 32278 [var. XIIIe s.]: judas macabre).
(Orig. controversial (see FEW, t. 6, 1, pp. 2a-3a). The Oriental etymologies that have been proposed (ar. maqbara, maqbura, plur.; "cemetery", v. VAN PRAET quoted by CHAMPOLLION-FIGEAC, op. cit., pp. 367-368; and Syrian meqabberêy, meqabr ey "gravediggers", v. Fr. mod. t. 15, pp. 96-98 and Romania t. 71, pp. 408-412), lacking foundation, it seems preferable to see Macabré (wrongly read macabre in the 19th century, see 1811, supra et Romania t. 18, p..513) as a variation of the proper name of the original Biblical Maccabee (cf. p. ex. ca 1190, GUY DE CAMBRAI, Vengement Alixaundre, ed. B. Edwards, p. 96, 1748 [var. 2nd half of 13th century]: Judas Macabrés; ca 1200, 2nd Continuation of Perceval, ed. W. Roach, t. 4, p. 500, 32278 [var. 13th c.]: judas macabre).
The entry goes on to describe four more specific hypotheses about why Maccabees may have been a source. The evidence is slight and doesn't address the Arabic or Syriac claims, and so it is omitted here.
The Arabic etymology is possible, but there is more direct evidence for connecting the form Macabre to something like "Judas Macabre" than there is for making a connection to an Arabic or Syriac root.