While browsing the web, I came across this page about Minangali (“a variety of Lower Tanudan Kalinga spoken in the town of Mangali, Kalinga Province, Philippines”), in that it possesses a consonant similar to Southern Catanduanes: “the interdental approximant, a rare speech sound found in about a dozen Philippine languages, including Kagayanen, Karaga Mandaya, Kalagan, Southern Catanduanes Bicolano, and several varieties of Kalinga (Olson and Mielke 2007). ” Some words are given as an example.
|Minangali (Kalinga)||English||Bikol (possible cognate)||Tagalog (possible cognate)|
|laḻaki||man (adult male)||lalaki||lalake|
|bukoḻ||seed||bukol (lump)||bukol (lump)|
|anaddaḻan||walk||dalan (way)||daan (way)|
From the examples, it would be noted that the sound is never beside an i, or never a word initial sound but can be found syllable initial (word-medial) and syllable final. It would also seem that its counterpart is l in Bikol and Tagalog, with only 3 words (blood, hear, ashes) showing a g.
Further study of the sound is in here. The study described the manner of articular as approximant but noted that it is “L-colored”, thus making it an interdental lateral approximant. The more common lateral in other Philippine languages is an alveolar lateral approximant. The study also noted that it has a complementary distribution in Kagayanen with l, where l occurs word initially, or contiguous to i. It has the following reflexes in other languages: [ɣ] Aklanon, Buhi’non; [ɻ] Madukayong Kalinga, Balangao, Mansaka, Upper Tanudan Kalinga; and [ɭ] Southern Kalinga. Some of the words mentioned there are: [uð̞u] ‘head’ and [pað̞ad] ‘palm’ . It’s hypothesized to have been a retention from proto-Philippine (Western Malayo Polynesian?). The sound is endangered due to pressure from outsiders who mock the use of the sound, so speakers avoid using the sound with outsiders.
In Aklanon, the sound is not in complementary disctibution with l, nor its not found at word initial, as here exemplified: [ɣinapas] (Bikol: linapas, Tagalog: sinuway); [ɣinamon] (Bikol: linamon, Tagalog: nilamon); and [ɣinuboŋ] (Bikol: linubong, Tagalog: nilibing). Although in the word bases of those examples, the i does not follow the [ɣ] but in here, it says it rarely occurs with i, which means that it does occur with i. And this gives an example of contrast:
[lasaw] – “syrup” (Bikol: tangguli, Tagalog: pulot) [ɣasaw]- “not sticky, watery" (Bikol: lasaw, Tagalog: lasaw)
I would be excited if true is if Bikol Miraya, a dialect spoken in and around Camalig Albay, also has this sound according to that page, but that is never corroborated in other linguistic studies of Bikol dialects. One word mentioned there is aļe’ (Bikol Naga: igwa)