A confused entry. The glossing verb sugkateti/qento is drawn from the Homeric scholia, but as a gloss for e)pih/|neon ('they were praising', 'they were agreeing to'), rather than for e)penh/neon ('were piling on/up'). See the scholia to Homer, Iliad 3.461 (web address 1) and 4.380 (web address 2), and also epsilon 2186 where the gloss is quoted correctly.
Fueling the lexicographer's confusion may be the fact that although the middle-voice forms of sugkatati/qhmi regularly mean 'put in with' in the sense of 'get behind' or 'join in supporting', active forms of the same verb can mean 'put (something) together with', and hence might serve as an appropriate gloss for a verb that means 'pile up'. Also, Homer sometimes uses e)ph/|neon in tmesis (e)pi\ d' h)/|neon epsilon 2295), including at Iliad 3.461, the scholia to which may be the source for the gloss (cf. Odyssey 12.294, 12.352). In manuscript this might appear as epidhneon, which could conceivably be misread as e)pinh/neon or e)penh/neon. The headword does occur in Homer, e.g. Iliad 7.428 (web address 3).